Budgerigar mutations

Genetics of Base Color

Summary:
Yellow-base - dominant
White-base - recessive

There are only two alleles for a budgie's base color: yellow-based and white-based. The yellow-based allele is dominant to the recessive white-based allele. Here, we will represent the yellow-based gene as "B" and the white-based gene as "b". Therefore there are three possible genetic combinations for any budgie:

• BB - Two yellow-base genes (homozygous) resulting in a yellow-based budgie.
• Bb - One yellow-base gene and one white-base gene (heterozygous) resulting in a yellow-based budgie that is "split" for white-base.
• bb - Two white-base genes (homozygous) resulting in a white-based budgie.

As you can see, the only way that a budgie will be white-based is if both of it's genes are the recessive white-base. If the yellow-base gene accompanies the white-base gene, the budgie will be yellow-based because the yellow-base gene is dominant. Such a budgie is heterozygous and is said to be "split" for white-base, which means it carries the recessive gene, but does not show it because of the presence of the dominant gene. Breeding two yellow-based budgies who are split for white-base can result in white-based budgies. However, it is difficult to tell if a budgie is split for white-base. It is said that if there is blue in the feathers around the vent of a normal yellow-based budgie, it is split for white-base. Either knowing the varieties of the parents or selective breeding can reveal the genetics of a particular bird. Below are Punnet square examples of possible pairings.

Two homozygous yellow-based budiges BBXBB B B B BB BB B BB BB Offspring Phenotype Results: 100% Yellow-based Offspring Genotype Results: 100% Homozygous dominant (BB)	A homozygous yellow-based budgie and a heterozygous (split for white-base) yellow-based budgie BBXBb B B B BB BB b Bb Bb Offspring Phenotype Results: 100% Yellow-based Offspring Genotype Results: 50% Homozygous dominant (BB) 50% Heterozygous (Bb)
Two heterozygous yellow-based budgies (both split for white-base) BbXBb B b B BB Bb b Bb bb Offspring Phenotype Results: 75% Yellow-based 25% White-based Offspring Genotype Results: 50% Heterozygous (Bb) 25% Homozygous dominant (BB) 25% Homozygous recessive (bb)	A homozygous yellow-based budige and a white-based budgie BBXbb B B b Bb Bb b Bb Bb Offspring Phenotype Results: 100% Yellow-based Offspring Genotype Results: 100% Heterozygous (Bb)
A heterozygous (split for white-base) yellow-based budige and a white-based budgie BbXbb B b b Bb bb b Bb bb Offspring Phenotype Results: 50% Yellow-based 50% White-based Offspring Genotype Results: 50% Heterozygous (Bb) 50% Homozygous recessive (bb)	Two white-based budgies bbxbb b b b bb bb b bb bb Offspring Phenotype Results: 100% White-based Offspring Genotype Results: 100% Homozygous recessive (bb)

Genetics of Dark Factor

Summary:
Dark factor - semi-dominant
Normal - recessive

There are only two alleles that determine the darkness of a budgies body color: the normal gene and the dark factor gene. The dark factor gene is semi-dominant to the recessive normal gene. This means that a budgie that has one dark factor and one normal gene looks different from a budgie that has two dark factor genes. Here, we will represent the dark factor gene as "D" and the normal gene as "d". Therefore there are three possible genetic combinations for any budgie:

• dd - Two normal genes (homozygous) resulting in a normal light colored budgie (light green or sky blue).
• Dd - One dark factor gene and one normal gene (heterozygous) resulting in a single dark factor budgie (dark green or cobalt).
• DD - Two dark factor genes (homozygous) resulting in a double dark factor budgie (olive or mauve).

As you can see, the darkness of a budgie occurs in degrees, depending on the number of dark factors present. Below are punnet squares of some (but not all) possible pairings.

Two light (no dark factor) budgies (light green or sky blue) ddXdd d d d dd dd d dd dd Offspring Phenotype Results: 100% Light (no dark factor) Offspring Genotype Results: 100% Homozygous recessive (dd)	Two single dark factor budgies (dark green or cobalt) DdXDd D d D DD Dd d Dd dd Offspring Phenotype Results: 25% Double dark factor 50% Single dark factor 25% Light (no dark factor) Offspring Genotype Results: 25% Homozygous dominant (DD) 50% Heterozygous (Dd) 25% Homozygous recessive (dd)
A double dark factor bugie (olive or mauve) and a light (no dark factor) budgie (light green or sky blue) DDXdd D D d Dd Dd d Dd Dd Offspring Phenotype Results: 100% Single dark factor Offspring Genotype Results: 100% Heterozygous (Dd)	A light (no dark factor) budige (light green or sky blue) and a single dark factor budgie (dark green or cobalt) ddXDd d d D Dd dd d Dd dd Offspring Phenotype Results: 50% Single dark factor 50% Light (no dark factor) Offspring Genotype Results: 50% Heterozygous (Dd) 50% Homozygous recessive (dd)

Genetics of Grey Factor

Summary:
Grey Factor - dominant
Normal - recessive

There are only two alleles for the grey trait: the grey factor gene and the normal gene. The grey factor gene is completely dominant to the recessive normal gene. This means that a single-factor grey looks the same as the double-factor grey. Here, we will represent the grey gene as "G" and the normal gene as "g". Therefore there are three possible genetic combinations for any budgie:

• gg - Two normal genes (homozygous) resulting in a normal budgie.
• Gg - One grey factor gene and one normal gene (heterozygous) resulting in a grey factor budgie that is genetically single-factor.
• GG - Two grey factor genes (homozygous) resulting in a grey factor budgie that is genetically double-factor.

As you can see, it only takes one grey gene for a budgie to display the grey factor. This makes this is an easy variety to breed. Grey factor creates grey-green in yellow-based budgies and grey in white-based budgies. Below are some punnet square examples of pairings. A budgie described as "grey factor," "single factor grey," or "double factor grey" can either be yellow-based (grey green) or white-based (grey).

A normal budgie and a single factor grey budgie ggXGg g g G Gg Gg g gg gg Offspring Phenotype Results: 50% Grey Factor 50% Normal Offspring Genotype Results: 50% Heterozygous (Gg) 50% Homozygous recessive (gg)	A normal budgie and a double-factor grey budgie ggXGG g g G Gg Gg G Gg Gg Offspring Phenotype Results: 100% Grey Factor Offspring Genotype Results: 100% Heterozygous (Gg)
Two single-factor grey budgies GgXGg G g G GG Gg g Gg gg Offspring Phenotype Results: 75% Grey Factor 25% Normal Offspring Genotype Results: 50% Heterozygous (Gg) 25% Homozygous dominant (GG) 25% Homozygous recessive (gg)	A single factor grey budgie and a double factor grey budgie GgXGG G g G GG Gg G GG Gg Offspring Phenotype Results: 100% Grey Factor Offspring Genotype Results: 50% Homozygous dominant (GG) 50% Heterozygous (Gg)

Genetics of Violet Factor

Summary:
Violet Factor - semi-dominant
Normal - recessive

There are only two alleles for the violet trait: the violet factor gene and the normal gene. The violet factor gene is semi-dominant to the recessive normal gene. Because it is semi-dominant, in some cases a single-factor violet looks different from a double-factor violet. Here, we will represent the violet gene as "V" and the normal gene as "v". Therefore there are three possible genetic combinations for any budgie:

• vv - Two normal genes (homozygous) resulting in a normal budgie.
• Vv - One violet factor gene and one normal gene (heterozygous) resulting in a violet budgie only in cobalts and slightly detectable violet undertones in greens, sky blues, and mauves.
• VV - Two violet factor genes (homozygous) resulting in a violet budgie in cobalts and sky blues and detectable violet undertones in greens and mauves.

As you can see, the presence of one violet factor causes violet coloration in a budgie, but only causes true violet body color in cobalt budgies (budgies with one dark factor). Two violet factors cause the violet coloration in budgies to be more visible, but only causes true violet body color in cobalts and sky blues. It is difficult to breed true violets because of the conditions required to obtain the true violet body color. You can usually tell a green budgie has at least one violet factor. The violet darkens the green body color and sometimes causes violet to show in the feathers near the feet and vent. The feet may also look very dark or purple. Single-factor violet sky blues are darker that normal sky blues and usually show some violet coloration on the body feathers near the feet and vent. It is very difficult to tell if a mauve has the violet factor. Below are some punnet square examples of pairings.

Basic Violet Inheritance Patterns

A normal budgie and a single factor violet budgie vvXVv v v V Vv Vv v vv vv Offspring Phenotype Results: 50% Single-Factor Violet 50% Normal Offspring Genotype Results: 50% Heterozygous (Vv) 50% Homozygous recessive (vv)	A normal budgie and a double-factor violet budgie vvXVV v v V Vv Vv V Vv Vv Offspring Phenotype Results: 100% Single-Factor Violet Offspring Genotype Results: 100% Heterozygous (Vv)
Two single-factor violet budgies VvXVv V v V VV Vv v Vv vv Offspring Phenotype Results: 25% Double-Factor Violet 50% Single-Factor Violet 25% Normal Offspring Genotype Results: 50% Heterozygous (Vv) 25% Homozygous dominant (VV) 25% Homozygous recessive (vv)	A single factor violet budgie and a double factor grey budgie VvXVV V v V VV Vv V VV Vv Offspring Phenotype Results: 50% Double-Factor Violet 50% Single-Factor Violet Offspring Genotype Results: 50% Homozygous dominant (VV) 50% Heterozygous (Vv)
Advanced Violet Inheritance Patterns: (Inheritance Patterns of both the Dark Factor and Violet Factor)
Two violet budgies (both cobalt, single-factor violet) DdVvXDdVv DV Dv dV dv DV DDVV DDVv DdVV DdVv Dv DDVv DDvv DdVv Ddvv dV DdVV DdVv ddVV ddVv dv DdVv Ddvv ddVv ddvv Offspring Phenotype Results: 37.5% True Violet (Cobalt Violet) 18.75% Mauve Violet 12.5% Sky Blue Single-Factor Violet 12.5% Cobalt 6.25% Mauve 6.25% Sky Blue 6.25% True Violet (Sky Blue Double-Factor Violet)	A sky blue budgie and a violet budgie (cobalt, single-factor violet) ddvvXDdVv dv dv dv dv DV DdVv DdVv DdVv DdVv Dv Ddvv Ddvv Ddvv Ddvv dV ddVv ddVv ddVv ddVv dv ddvv ddvv ddvv ddvv Offspring Phenotype Results: 25% True Violet (Cobalt Violet) 25% Cobalt 25% Sky Blue Single-Factor Violet 25% Sky Blue

Genetics of Dilution

Summary:
Normal - dominant
Greywing - recessive, co-dominant with clearwing
Clearwing - recessive, co-dominant with greywing
Dilute - recessive

There are four dilution alleles: normal, greywing, clearwing, and dilute. The normal allele is dominant to all other alleles. Greywing and clearwing are both recessive to normal and dominant to dilute. Greywing and clearwing are co-dominant with each other, which means they do not completely dominate over each other and both affect the budgie's phenotype when present. Dilute is recessive to all other alleles.

The dilute mutation can be confusing since there are three non-normal alleles which make four different phenotypes. This is how it works: Greywing and clearwing are co-dominant. The greywing gene by itself produces more pigment in the wings, causing the grey colored markings, and less pigment in the body feathers, causing 50% color dilution. The clearwing gene by itself produces less pigment in the wings, causing very light markings, and more pigment in the body feathers, causing the bright body color. When a budgie has both a greywing and a clearwing gene, the budgie is a full-body-color greywing. The greywing gene makes up for the lack of wing pigmentation ability of the clearwing gene, and the clearwing gene makes up for the lack of body feather pigmentation ability of the greywing gene.
So when a budgie is homozygous greywing or has a greywing gene with the recessive dilute gene, the budgie has the grey wing markings and diluted body color. When a budgie is homozygous clearwing or has the clearwing gene with the recessive dilute gene, the budgie has very light wing markings and a bright body color. When a budgie has both the greywing and clearwing gene, it is a full-body-color greywing with grey wing markings and bright body color. When a budgie has two of the recessive dilute genes it shows the traits of dilute with about 70% washed out markings/color all over.

Here, "C" represents the normal gene, "c^g" represents the greywing gene, "c^w" represents the clearwing gene, and "c^d" represents the dilute gene. With these four alleles we have the following possible genotypes:

• CC, Cc^g, Cc^w, Cc^d - Two normal genes or one normal gene and any of the recessive genes, resulting in a normal budgie.
• c^gc^g, c^gc^d - Two greywing genes or one greywing gene and a dilute gene, resulting in a greywing budgie.
• c^gc^w - One greywing gene and one clearwing gene, resulting in a full-body-color greywing budgie.
• c^wc^w, c^wc^d - Two clearwing genes or one clearwing gene and one dilute gene, resulting in a clearwing budgie.
• c^dc^d - Two dilute genes, resulting in a dilute budgie.

As you can see there are only five phenotype possibilities but many possible genetic combinations. It is key to remember that greywing and clearwing are co-dominant. The normal greywing has grey marking and 50% body color dilution. The normal clearwing has very light markings and no body color dilution. When the greywing and the clearwing gene are both present, we get the full-body-color greywing, which has the grey markings of the greywing mutation and the body color of the clearwing mutation. Other than the co-dominant relationship between greywing and clearwing, all other combinations work in a dominant-recessive relationship. The normal gene will prevail in the presence of any of the other recessive alleles. The greywing gene prevails when the dilute gene is present. The clearwing gene prevails when the dilute gene is present. Only when both genes are dilute does the dilute phenotype show up since dilute is recessive to all the other alleles. Below are Punnet square examples of some possible pairings. From these you can see that breeding the different dilution varieties can get pretty complicated.

A homozygous normal and a dilute CCXcdcd C C cd Ccd Ccd cd Ccd Ccd Offspring Phenotype Results: 100% Normal Offspring Genotype Results: 100% Heterozygous: normal split for dilute (Ccd)	A homozygous greywing and a homozygous clearwing cgcgXcwcw cg cg cw cgcw cgcw cw cgcw cgcw Offspring Phenotype Results: 100% Full-body-color greywings Offspring Genotype Results: 100% Heterozygous: greywing with clearwing (cgcw)
A greywing split for dilute and a clearwing split for dilute cgcdXcwcd cg cd cw cgcw cwcd cd cgcd cdcd Offspring Phenotype Results: 25% Full-body-color greywing 25% Greywing 25% Clearwing 25% Dilute Offspring Genotype Results: 25% Heterozygous - greywing with clearwing (cgcw) 25% Heterozygous - greywing split for dilute (cgcd) 25% Heterozygous - clearwing split for dilute (cwcd) 25% Homozygous recessive (cdcd)	Two full-body-color greywings cgcwXcgcw cg cw cg cgcg cgcw cw cgcw cwcw Offspring Phenotype Results: 50% Full-body-color greywing 25% Greywing 25% Clearwing Offspring Genotype Results: 50% Heterozygous - greywing with clearwing (cgcw) 25% Homozygous - greywing (cgcg) 25% Homozygous - clearwing (cwcw)
A dilute budgie and a normal budgie split for dilute cdcdXCcd cd cd C Ccd Ccd cd cdcd cdcd Offspring Phenotype Results: 50% Normal 50% Dilute Offspring Genotype Results: 50% Heterozygous - normal split for dilute (Ccd) 50% Homozygous recessive (cdcd)	A normal budgie split for greywing and a normal budgie split for dilute CcgxCcd C cg C CC Ccg cd Ccd cgcd Offspring Phenotype Results: 75% Normal 25% Greywing Offspring Genotype Results: 25% Homozygous dominant (CC) 25% Heterozygous - normal split for greywing (Ccg) 25% Heterozygous - normal split for dilute (Ccd) 25% Heterozygous - greywing split for dilute (cgcd)

Yellowface

Yellowface budgies are in between yellow-based budgies and white-based budgies. There are different degrees of the level of yellow pigment, less than the yellow-based variety. These different levels of yellow pigment are caused by several different genes. Visually, there are two types of yellow face: Type I and Type II. In type I yellowface budgies, the mask feathers are all yellow. The yellow may also show up in the peripheral tail feathers. The yellow is confined to these areas only and the budgie is normally colored in the body feathers. Type II yellowface budgies have yellow in the mask feathers and tail, just like the type I. However, after the first molt at 3 months of age, the yellow diffuses into the body color and creates a new color, depending on the original color. In the case of the sky blue variety, as seen below, the type II yellowface creates a seafoam green color, but in the type I yellowface the body color remains sky blue.

Basic Genetics:
Complicated!

Genetics of Lutino & Albino (Ino)

Summary:
Ino - sex-linked recessive
Normal - dominant

Lutino/albino (ino) is a sex-linked mutation. This means that the gene is located on the Z-chromosome. Male budgies have two Z-chromosomes (ZZ) and female budgies have a Z-chromosome and a W-chromosome (ZW). Since the gene is recessive to normal, male budgies must have two ino genes (one on each Z-chromosome) to be an ino variety. However, since female budgies have only one Z-chromosome, if their Z-chromosome has the ino gene, they will be the ino variety. It is because females need only one gene to express the trait that sex-linked mutations such as ino are more common in female budgies. Here, we will represent the ino gene on the Z-chromosome as "Zⁱ" and the Z-chromosome with the normal gene as "Z". There are three genotype possibilities for a male budgie:

• ZZ - Two normal genes resulting in a normal male budgie.
• ZZⁱ - One normal gene and one ino gene resulting in a normal male budgie that is split for ino.
• ZⁱZⁱ - Two ino genes resulting in an ino male budgie.

And there are two genotype possibilities for a female budgie:

• ZW - A normal gene resulting in a normal female budgie.
• ZⁱW - An ino gene resulting in an ino female budgie.

Below are some punnet square examples of pairings. As you will see, if your goal is to breed a sex-linked mutation like ino, besides breeding two visually ino budgies, the best results will be from the pairing of a male who is split for ino to an ino female.

A normal male budgie and an ino female budgie ZZ x ZiW Z Z Zi ZZi ZZi W ZW ZW Offspring Phenotype Results: Males: 100% Normal Females: 100% Normal Offspring Genotype Results: 50% Male split for ino (ZZi) 50% Female normal (ZW)	An ino male budgie and a normal female budgie ZiZi x ZW Zi Zi Z ZZi ZZi W ZiW ZiW Offspring Phenotype Results: Males: 100% Normal Females: 100% Ino Offspring Genotype Results: 50% Male split for ino (ZZi) 50% Female ino (ZiW)
A male split for ino budgie and a normal female ZZi x ZW Z Zi Z ZZ ZZi W ZW ZiW Offspring Phenotype Results: Males: 100% Normal Females: 50% Ino, 50% Normal Offspring Genotype Results: 25% Male normal (ZZ) 25% Male split for ino (ZZi) 25% Female normal (ZW) 25% Female ino (ZiW)	A male split for ino and a female ino budgie ZZi x ZiW Z Zi Zi ZZi ZiZi W ZW ZiW Offspring Phenotype Results: Males: 50% Ino, 50% Normal Females: 50% Ino, 50% Normal Offspring Genotype Results: 25% Male split for ino (ZZi) 25% Male ino (ZiZi) 25% Female normal (ZW) 25% Female ino (ZiW)

 Genetics of Opaline

Summary:
Opaline - sex-linked recessive
Normal - dominant

Opaline is a sex-linked mutation. This means that the gene is located on the Z-chromosome. Male budgies have two Z-chromosomes (ZZ) and female budgies have a Z-chromosome and a W-chromosome (ZW). Since the gene is recessive to normal, male budgies must have two opaline genes (one on each x-chromosome) to be an opaline variety. However, since female budgies have only one Z-chromosome, if their Z-chromosome has the opaline gene, they will be the opaline variety. It is because females need only one gene to express the trait that sex-linked mutations such as opaline are more common in female budgies. Here, we will represent the opaline gene on the Z-chromosome as "Z^o" and the Z-chromosome with the normal gene as "Z". There are three genotype possibilities for a male budgie:

• ZZ - Two normal genes resulting in a normal male budgie.
• ZZ^o - One normal gene and one opaline gene resulting in a normal male budgie that is split for opaline.
• Z^oZ^o - Two opaline genes resulting in an opaline male budgie.

And there are two genotype possibilities for a female budgie:

• ZW - A normal gene resulting in a normal female budgie.
• Z^oW - An opaline gene resulting in an opaline female budgie.

Below are some punnet square examples of pairings. As you will see, if your goal is to breed a sex-linked mutation like opaline, besides breeding two visually opaline budgies, the best results will be from the pairing of a male who is split for opaline to an opaline female.

A normal male budgie and an opaline female budgie ZZ x ZoW Z Z Zo ZZo ZZo W ZW ZW Offspring Phenotype Results: Males: 100% Normal Females: 100% Normal Offspring Genotype Results: 50% Male split for opaline (ZZo) 50% Female normal (ZW)	An opaline male budgie and a normal female budgie ZoZo x ZW Zo Zo Z ZZo ZZo W ZoW ZoW Offspring Phenotype Results: Males: 100% Normal Females: 100% Opaline Offspring Genotype Results: 50% Male split for opaline (ZZo) 50% Female opaline (ZoW)
A male split for opaline budgie and a normal female ZZo x ZW Z Zo Z ZZ ZZo W ZW ZoW Offspring Phenotype Results: Males: 100% Normal Females: 50% Opaline, 50% Normal Offspring Genotype Results: 25% Male normal (ZZ) 25% Male split for oplaine (ZZo) 25% Female normal (ZW) 25% Female opaline (ZoW)	A male split for opaline and a female opaline budgie ZZo x ZoW Z Zo Zo ZZo ZoZo W ZW ZoW Offspring Phenotype Results: Males: 50% Opaline, 50% Normal Females: 50% Opaline, 50% Normal Offspring Genotype Results: 25% Male split for opaline (ZZo) 25% Male opaline (ZoZo) 25% Female normal (ZW) 25% Female opaline (ZoW)

Genetics of Spangle

Summary:
Spangle - dominant
Normal - recessive

There are only two alleles for spangle: the spangle gene and the normal gene. The spangle gene is semi-dominant to the recessive normal gene. This means that a single-factor spangle looks different from the double-factor spangle. Here, we will represent the spangle gene as "S" and the normal gene as "s". Therefore there are three possible genetic combinations for any budgie:

• ss - Two normal genes (homozygous) resulting in a normal budgie.
• Ss - One spangle gene and one normal gene (heterozygous) resulting in a spangled budgie.
• SS - Two spangle genes (homozygous) resulting in a double-factor spangle budgie, which has no markings or color.

As you can see, it is only when one spangle gene and one normal gene is present that a budgie is the actual spangle variety. When two spangle genes are present the budgie has no markings or color, and looks like a lutino/albino except for the red eyes. Below are some punnet square examples of pairings.

A normal budgie and a spangle budgie ssXSs s s S Ss Ss s ss ss Offspring Phenotype Results: 50% Spangle 50% Normal Offspring Genotype Results: 50% Heterozygous (Ss) 50% Homozygous recessive (ss)	A normal budgie and a double-factor spangle budgie ssXSS s s S Ss Ss S Ss Ss Offspring Phenotype Results: 100% Spangle Offspring Genotype Results: 100% Heterozygous (Ss)
Two spangle budgies SsXSs S s S SS Ss s Ss ss Offspring Phenotype Results: 25% Double-Factor Spangle 50% Spangle 25% Normal Offspring Genotype Results: 50% Heterozygous (Ss) 25% Homozygous dominant (SS) 25% Homozygous recessive (ss)	A spangle budgie and a double-factor spangle budgie SsXSS S s S SS Ss S SS Ss Offspring Phenotype Results: 50% Double-Factor Spangle 50% Spangle Offspring Genotype Results: 50% Homozygous dominant (SS) 50% Heterozygous (Ss)

Genetics of Cinnamon

Summary:
Cinnamon - sex-linked recessive
Normal - dominant

Cinnamon is a sex-linked mutation. This means that the gene is located on the Z-chromosome. Male budgies have two Z-chromosomes (ZZ) and female budgies have a Z-chromosome and a W-chromosome (ZW). Since the gene is recessive to normal, male budgies must have two cinnamon genes (one on each Z-chromosome) to be a cinnamon variety. However, since female budgies have only one Z-chromosome, if their Z-chromosome has the cinnamon gene, they will be the cinnamon variety. It is because females need only one gene to express the trait that sex-linked mutations such as cinnamon are more common in female budgies. Here, we will represent the cinnamon gene on the Z-chromosome as "Z^c" and the Z-chromosome with the normal gene as "Z". There are three genotype possibilities for a male budgie:

• ZZ - Two normal genes resulting in a normal male budgie.
• ZZ^c - One normal gene and one cinnamon gene resulting in a normal male budgie that is split for cinnamon.
• Z^cZ^c - Two cinnamon genes resulting in a cinnamon male budgie.

And there are two genotype possibilities for a female budgie:

• ZW - A normal gene resulting in a normal female budgie.
• Z^cW - A cinnamon gene resulting in a cinnamon female budgie.

Below are some punnet square examples of pairings. As you will see, if your goal is to breed a sex-linked mutation like cinnamon, besides breeding two visually cinnamon budgies, the best results will be from the pairing of a male who is split for cinnamon to a cinnamon female.

A normal male budgie and a cinnamon female budgie ZZ x ZcW Z Z Zc ZZc ZZc W ZW ZW Offspring Phenotype Results: Males: 100% Normal Females: 100% Normal Offspring Genotype Results: 50% Male split for cinnamon (ZZc) 50% Female normal (ZW)	A cinnamon male budgie and a normal female budgie ZcZc x ZW Zc Zc Z ZZc ZZc W ZcW ZcW Offspring Phenotype Results: Males: 100% Normal Females: 100% Cinnamon Offspring Genotype Results: 50% Male split for cinnamon (ZZc) 50% Female cinnamon (ZcW)
A male split for cinnamon budgie and a normal female ZZc x ZW Z Zc Z ZZ ZZc W ZW ZcW Offspring Phenotype Results: Males: 100% Normal Females: 50% Cinnamon, 50% Normal Offspring Genotype Results: 25% Male normal (ZZ) 25% Male split for cinnamon (ZZc) 25% Female normal (ZW) 25% Female cinnamon (ZcW)	A male split for cinnamon and a female cinnamon budgie ZZc x ZcW Z Zc Zc ZZc ZcZc W ZW ZcW Offspring Phenotype Results: Males: 50% Cinnamon, 50% Normal Females: 50% Cinnamon, 50% Normal Offspring Genotype Results: 25% Male split for cinnamon (ZZc) 25% Male cinnamon (ZcZc) 25% Female normal (ZW) 25% Female cinnamon (ZcW)

Genetics of Dominant Pied

Summary:
Dominant Pied - dominant
Normal - recessive

There are only two alleles for dominant pied: the normal gene and the dominant pied gene. The dominant pied gene is semi-dominant to the recessive normal gene. This means that a single-factor dominant pied looks different from the double-factor dominant pied. A single-factor dominant pied, the classic dominant pied, usually has the standard markings with the band across the tummy and bottom of the wings. A double-factor dominant pied's clear areas are extended, leaving a budgie with more clear areas than those that are left normally marked. Here, we will represent the dominant pied gene as "T" and the normal gene as "t". Therefore there are three possible genetic combinations for any budgie:

• tt - Two normal genes (homozygous) resulting in a normal budgie.
• Tt - One dominant pied gene and one normal gene (heterozygous) resulting in a single-factor dominant pied with the standard dominant pied markings.
• TT - Two dominant pied genes (homozygous) resulting in a double-factor dominant pied budgie, with few normal markings.

As you can see, it only takes one dominant pied gene for a budgie to display the dominant pied traits. This makes this is an easy variety to breed. Below are some punnet square examples of pairings.

A normal budgie and a single-factor dominant pied ttXTt t t T Tt Tt t tt tt Offspring Phenotype Results: 50% Dominant Pied 50% Normal Offspring Genotype Results: 50% Heterozygous (Tt) 50% Homozygous recessive (tt)	A normal budgie and a double-factor dominant pied ttXTT t t T Tt Tt T Tt Tt Offspring Phenotype Results: 100% Dominant Pied Offspring Genotype Results: 100% Heterozygous (Tt)
Two single-factor dominant pieds TtXTt T t T TT Tt t Tt tt Offspring Phenotype Results: 25% Double-Factor Dominant Pied 50% Dominant Pied 25% Normal Offspring Genotype Results: 25% Homozygous dominant (TT) 50% Heterozygous (Tt) 25% Homozygous recessive (tt)	A single factor dominant pied budgie and a double factor dominant pied budgie TtXTT T t T TT Tt T TT Tt Offspring Phenotype Results: 50% Double-Factor Dominant Pied 50% Dominant Pied Offspring Genotype Results: 50% Homozygous dominant (TT) 50% Heterozygous (Tt)

Genetics of Recessive Pied

Summary:
Normal - dominant
Recessive Pied - recessive

There are only two alleles for recessive pied: the normal gene and the recessive pied gene. The normal gene is completely dominant to the recessive pied gene. Here, we will represent the normal gene as "R" and the recessive pied gene as "r". Therefore there are three possible genetic combinations for any budgie:

• RR - Two normal genes (homozygous) resulting in a normal budgie.
• Rr - One normal gene and one recessive pied gene (heterozygous) resulting in a normal budgie that is split for recessive pied.
• rr - Two recessive pied genes (homozygous) resulting in a recessive pied budgie.

As you can see, the only was a budgie can show the recessive pied trait is if it has two recessive pied genes. If the normal allele is present, the budgie will look normal and is said to be "split" for recessive pied. Below are some punnet square examples of pairings.

A normal homozygous budgie and a recessive pied RRXrr R R r Rr Rr r Rr Rr Offspring Phenotype Results: 100% Normal Offspring Genotype Results: 100% Heterozygous (Rr)	Two normal split for recessive pied budgies RrXRr R r R RR Rr r Rr rr Offspring Phenotype Results: 75% Normal 25% Recessive Pied Offspring Genotype Results: 50% Heterozygous (Rr) 25% Homozygous dominant (RR) 25% Homozygous recessive (rr)
A normal split for recessive pied budgie and a recessive pied budgie RrXrr R r r Rr rr r Rr rr Offspring Phenotype Results: 50% Normal 50% Recessive Pied Offspring Genotype Results: 50% Heterozygous (Rr) 50% Homozygous recessive (rr)	Two recessive pied budgies rrXrr r r r rr rr r rr rr Offspring Phenotype Results: 100% Recessive Pied Offspring Genotype Results: 100% Homozygous recessive (rr)

Genetics of Clearflight Pied

Summary:
Clearflight Pied - dominant
Normal - recessive

The inheritance pattern of clearflight pied is the same as dominant pied. However, clearflight pied is unrelated to either dominant pied or recessive pied, and a budgie can have any combination of the three pieds at the same time. There are only two alleles for clearflight pied: the normal gene and the clearflight pied gene. The clearflight pied gene is completely dominant to the recessive normal gene. This means that a single-factor clearflight pied looks the same as the double-factor clearflight pied. Here, we will represent the clearflight pied gene as "P" and the normal gene as "p". Therefore there are three possible genetic combinations for any budgie:

• pp - Two normal genes (homozygous) resulting in a normal budgie.
• Pp - One clearflight pied gene and one normal gene (heterozygous) resulting in a visually clearflight pied budgie that is single-factor.
• PP - Two clearflight pied genes (homozygous) resulting in a visually clearflight pied budgie that is double-factor.

As you can see, it only takes one clearflight pied gene for a budgie to display the clearflight pied traits. This makes this is an easy variety to breed. Below are some punnet square examples of pairings.

A normal budgie and a single-factor clearflight pied ppXPp p p P Pp Pp p Pp Pp Offspring Phenotype Results: 50% Clearflight Pied 50% Normal Offspring Genotype Results: 50% Heterozygous (Pp) 50% Homozygous recessive (pp)	A normal budgie and a double-factor clearflight pied ppXPP p p P Pp Pp P Pp Pp Offspring Phenotype Results: 100% Clearflight Pied Offspring Genotype Results: 100% Heterozygous (Pp)
Two single-factor clearflight pieds PpXPp P p P PP Pp p Pp pp Offspring Phenotype Results: 75% Clearflight Pied 25% Normal Offspring Genotype Results: 50% Heterozygous (Pp) 25% Homozygous dominant (PP) 25% Homozygous recessive (pp)	A single factor clearflight pied budgie and a double factor clearflight pied budgie PpXPP P p P PP Pp P PP Pp Offspring Phenotype Results: 100% Clearflight Pied Offspring Genotype Results: 50% Homozygous dominant (PP) 50% Heterozygous (Pp)

Genetics of Dark-Eyed Clear

Summary:
Clearflight Pied - dominant
Normal - recessive

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Recessive Pied - recessive
Normal - dominant

The dark-eyed clear variety is actually the result of the combination of two independent varieties: clearflight pied and recessive pied. Both the clearflight trait and recessive pied trait must be present in a budgie for it to be a dark-eyed clear. The clearflight pied gene is dominant, therefore a budgie with at least one clearflight gene will express the clearflight trait. The recessive pied gene is recessive, therefore a budgie must have two recessive pied genes to express the recessive pied trait. Here, we will represent the clearflight pied gene as "P" and the corresponding normal gene as "p". The recessive pied gene will be represented by "r" and the corresponding normal gene as "R". It is possible to determine what certain pairings will produce with respect to dark-eyed clears by learning the inheritance patterns of clearflight and recessive pied. However, since the dark-eyed clear is an intriguing variety that breeders may wish to try their hand at, below are some punnet square examples of pairings. Note: S-F is short for single-factor, D-F is short for double-factor, rec. stands for recessive, and DEC stands for dark-eyed clear.

Inheritance Patterns of both Clearflight Pied and Recessive Pied

A s-f clearflight pied budgie and a recessive pied budgie PpRRXpprr PR PR pR pR pr PpRr PpRr ppRr ppRr pr PpRr PpRr ppRr ppRr pr PpRr PpRr ppRr ppRr pr PpRr PpRr ppRr ppRr Offspring Phenotype Results: 50% Clearflight Pied 50% Normal Offspring Genotype Results: 50% S-F clearflight, split for rec. pied (PpRr) 50% Normal, split for rec. pied (ppRr)	A s-f clearflight pied split for rec. pied budgie and a recessive pied budgie PpRrXpprr PR Pr pR pr pr PpRr Pprr ppRr pprr pr PpRr Pprr ppRr pprr pr PpRr Pprr ppRr pprr pr PpRr Pprr ppRr pprr Offspring Phenotype Results: 25% Clearflight Pied 25% Dark-Eyed Clear 25% Normal 25% Recessive Pied  Offspring Genotype Results: 25% S-F clearflight, split for rec. pied (PpRr) 25% DEC with s-f clearflight (Pprr) 25% Normal, split for rec. pied (ppRr) 25% Recessive pied (pprr)
Two s-f clearflight pied budgies, both split for rec. pied PpRrXPpRr PR Pr pR pr PR PPRR PPRr PpRR PpRr Pr PPRr PPrr PpRr Pprr pR PpRR PpRr ppRR ppRr pr PpRr Pprr ppRr pprr Offspring Phenotype Results: 56.25% Clearflight Pied 18.75% Dark-Eyed Clear 18.75% Normal 6.25% Recessive Pied Offspring Genotype Results: 25% S-F clearflight, split for rec. pied (PpRr) 12.5% D-F clearflight, split for rec. pied (PPRr) 12.5% S-F clearflight (PpRR) 12.5% Normal, split for rec. pied (ppRr) 12.5% DEC with s-f clearflight (Pprr) 6.25% DEC with d-f clearflight (PPrr) 6.25% Normal (ppRR) 6.25% Recessive pied (pprr) 6.25% D-F clearflight pied (PPRR)	A d-f clearflight pied budgie split for rec. pied and a recessive pied budgie PPRrXpprr PR Pr PR Pr pr PpRr Pprr PpRr Pprr pr PpRr Pprr PpRr Pprr pr PpRr Pprr PpRr Pprr pr PpRr Pprr PpRr Pprr Offspring Phenotype Results: 50% Clearflight Pied 50% Dark-Eyed Clear Offspring Genotype Results: 50% S-F clearflight, split for rec. pied (PpRr) 50% DEC with s-f clearflight (Pprr)
A dark-eyed clear budgie (with s-f clearflight) and a recessive pied budgie PprrXpprr Pr Pr pr pr pr Pprr Pprr pprr pprr pr Pprr Pprr pprr pprr pr Pprr Pprr pprr pprr pr Pprr Pprr pprr pprr Offspring Phenotype Results: 50% Dark-Eyed Clear 50% Recessive Pied Offspring Genotype Results: 50% DEC with s-f clearflight (Pprr) 50% Recessive pied (pprr)	A dark-eyed clear budgie (with s-f clearflight) and a s-f clearflight budgie split for recessive pied PprrXPpRr Pr Pr pr pr PR PPRr PPRr PpRr PpRr Pr PPrr PPrr Pprr Pprr pR PpRr PpRr ppRr ppRr pr Pprr Pprr pprr pprr Offspring Phenotype Results: 37.5% Dark-Eyed Clear 37.5% Clearflight Pied 12.5% Recessive Pied 12.5% Normal Offspring Genotype Results: 25% DEC with s-f clearflight (Pprr) 25% S-F clearflight, split for rec. pied (PpRr) 12.5% DEC with d-f clearflight (PPrr) 12.5% D-F clearflight, split for rec. pied (PPRr) 12.5% Normal, split for rec. pied (ppRr) 12.5% Recessive pied (pprr)
Two dark-eyed clear budgies (with s-f clearflight) PprrXPprr Pr Pr pr pr Pr PPrr PPrr Pprr Pprr Pr PPrr PPrr Pprr Pprr pr Pprr Pprr pprr pprr pr Pprr Pprr pprr pprr Offspring Phenotype Results: 75% Dark-Eyed Clear 25% Recessive Pied Offspring Genotype Results: 50% DEC with s-f clearflight (Pprr) 25% DEC with d-f clearflight (PPrr) 25% Recessive pied (pprr)

Crested

Crested is a unique mutation. In this variety, the feathers on the very top of the budgie's head point askew from normal, forming a crest. There are generally three types of crests. In the full-circular crest, the head feathers radiate in a full circle from a central point on the head, forming what may look like a Beatles haircut. In the half-circular crest, the feathers radiate from a central point only halfway or part way around the head. In the tufted crest, the feathers point up or backwards from the others near the front of the head, forming a tuft. There are also some variations of crested budgies where feathers on the back/wings grow askew and stick up.

Basic Genetics: Complicated!

Fallow

There are several types of fallow varieties, but in general, the fallow's head, wing, and tail markings are brownish. The body color is gradually diluted and is most visible on the rump. The eyes are red (some varieties do not have a pink iris, others do) and the cere of the male fallow does not change normally. Adult male fallows have purple ceres. Adult female fallows have the normal white/tan/brown ceres. This is a very beautiful specialist variety and is only seen in exhibition budgies.

Basic Genetics:
Normal - dominant
Fallow - recessive

Saddleback

In the saddleback variety, the budgie's stripes are dark grey on the head and into the "V" shaped area of the shoulders and top of the wings. The markings gradually return to the normal black at the bottom of the wings. The head markings are sparse. This variety looks similar to an opaline, however, unlike the opaline, the body color does not appear on the head or wings of the saddleback. The rest of the budgie's color and markings remain normal. This variety first appeared in 1975 in Australia and is still very rare.

Basic Genetics:
Normal - dominant
Saddleback - recessive

Texas Clearbody

In the Texas clearbody variety, the color of the budgie's body feathers is diffused or absent, and the wing markings are dark at the top and fade to a light grey toward the tips of the wings. The standard for the Texas clearbody budgie is to have no color in the body feathers, leaving only yellow or white (depending, of course, if the budgie is yellow-based or white-based). The Texas clearbody can however, have some color in the body feathers of up to a 50% dilution. In this case the body feather color is stronger toward the vent and rump feathers.

Basic Genetics:
Normal - sex-linked (Z chromosome), dominant to Clearbody - sex-linked, dominant to
Ino - sex-linked recessive

Slate

Slate is a color-adding factor similar to grey and violet. Slate produces a very dark bluish grey in white-based budgies. The darkness of the slate varies slightly according to the dark factor of the bird. Slate, like violet, can be present in a green (yellow-based) budgie, but only produces a darkening effect. True slate only appears on blue (white-based) budgies. This variety is extremely rare.

Basic Genetics:
Sex-linked (on the Z chromosome)

Anthracite

The anthracite budgie has a black (or very, very dark grey) body color. All other markings on the budgie are normal, except for the cheek patches, which are the same black as the body color. This variety is very new and was first established in Germany. This variety has been shown to be genetically semi-dominant. A single anthracite factor produces a darkening effect extremely similar to a single dark factor (producing cobalt). A budgie that is double-factor anthracite appears as the true anthracite with the black body color.

Basic Genetics:
Normal - recessive
Anthracite - semi-dominant

Blackface

Black face is a new mutation in which the black stripes (undulations) of the head extend all the way into the face and mask, as well as the body feathers. The blackface mutation also causes a darkening of the body color. This mutation is extremely rare and last known to only exist in the Netherlands.

Basic Genetics:
Normal - dominant
Blackface - recessive

Mottled

The mottled variety is extremely unique. A mottled budgie is hatched looking like a normal budgie. With each progressive molt, more and more of the budgie's feathers grow back clear. The budgie starts to look somewhat like a pied only with a more random, mottled pattern of clear feathers than the established varieties of pied. The amount of mottling an individual budgie has varies. Some have more normally marked and colored feathers than clear ones. Others eventually become almost all clear.

Basic Genetics:
Unknown/undetermined

Lacewing

Lacewing is a composite variety of lutino/albino and cinnamon. The budgie is mostly yellow (in yellow-based budgies) or mostly white (in white-based budgies). A suffusion of the body color is slightly visible in the body feathers. The markings of the head, wings, and tail show up as a light cinnamon color and the cheek patches are pale violet. The eyes are red/pink, and the cere of the male lacewing does not change normally. Adult male lacewings have purple ceres. Adult female lacewings have the normal white/tan/brown ceres. This variety is mostly only seen in exhibition budgies.

Basic Genetics:
See lutino/albino and cinnamon

 Half-Sider

The half-sider is actually not a true variety. The trait is not genetically inherited. Rather, it is a congenital condition. Visually, this budgie is split vertically, with the appearance and color of two distinct varieties appearing in splotches or sections divided by the vertical center line. I believe that this is a condition called tetragametic chimerism in which fraternal twin zygotes fuse at a very early stage in the womb, forming one individual with the tissues and DNA of both twins.

Basic Genetics:
NONE - This is a congenital condition

 Combinations

With all the different budgie mutations, the possible combinations are virtually limitless. Any individual budgie can have just about any combination of the mutations listed above. 

  

Copyrights:

Copy of Budgie Genetics

By Rebecca Cuzick
Budgie Genetics