IV. Turkey genes and comments

The literature pertaining to the genetics of the turkey is scant in comparison with the large body of work on chickens. Evidently the reasons for this are the relatively high cost of turkey research, the low reproductive rate and the significantly lower level of the economic importance of the turkey.

The discussion of poultry genetics in these pages is relevant to the turkey except for when specific genes for other poultry are being considered (for example, the sex-linked traits function the same as they do in chickens). Below is a table of genes and gene symbols specific to the turkey. The bronze turkey is the 'wild-type' and all genes that are different from the genes of the wild-type fowl are considered to be mutations. A superscript '+' indicates a gene possessed by the wild-type fowl. I have tried to incorporate relevant and interesting comments about these genes in the comment section. I continue to update this and correct it....

**Turkey Genes of Common Interest**
Sex-Linked Genes	Symbol	Comments
Narragansett	n	Recessive to N⁺ (below). Narragansett plumage color is a modification of bronze (wild-type) in which a steel-grey color replaces the iridescent red-green and copper bronzing.
Imperfect albinism	n^al	Recessive to N⁺ (below). Inhibits nearly all melanic pigment. Day-old poults had white down with discernable stripes. Poults can be blind. This gene is allelic with narragansett.
Bronze	N⁺	This is the gene that the bronze (wild-type) turkey has at the 'narragansett' locus.
Brown	e	Recessive. Gives brown pigmentation. The brown phenotype in the day-old poult has the same pattern as the bronze but the down is reddish-brown. The adult plumage pattern is the same as the bronze except that brown pigment is present in place of typical black and bronze. The presence of both brown (e) and narragansett(n) gives a light brown phenotype.
Late feathering	K	Dominant. Characterized by the absence of some or all of the primary flight feathers in poults at hatch. At maturity, late feathering birds often have few or no flight and tail feathers.
Bobber	bo	Recessive neurological mutation. Expresses between 14 and 21 days by cervical bending of the neck. Characterized by holding of the head between the legs. In a non-excited state, the bird is able to hold its head in a nearly normal position. If excited, the animal resumes the abnormal head position.
Vibrator	vi	Recessive neurological mutation characterized by rapid shaking of the head and neck. Trait expresses at hatch and diminishes with age to the point of being difficult to identify in adult birds.

**Autosomal Genes**
Autosomal Genes	Symbol	Comments
Bowed hocks	bh	Recessive. A genetically based leg-weakness affliction that is influenced by sex (but, not sex-linked). Males have a higher incidence than femalse.
Black	B	Dominant. Allelic to bronze (wild-type) and black-winged bronze. This gene causes black plumage. Poults carrying the black gene are characterized by black down without stripes. Some white may show in tips of flight and secondary feathers.
Black-winged bronze	b^l	Recessive. Allelic to bronze (wild-type) and black. Characterized by non-barring on the flight feathers in an otherwise bronze bird. The color intensity of the brown and black pigmentation is diminished in poults so that they down is nearly white.
White	c	Recessive. The homozygous fowl will have plumage color suppressed. This gene is allelic with grey and the wild-type gene (C⁺) which is dominant and allows the expression of plumage color.
Grey	c^g	Recessive to the wild-type, C⁺, and dominant to white, c. This gene is allelic to c and C⁺. The day-old poult is whitish-grey with a black strip on the back. The adult plumage is white with black barring except the flight feathers which have some black throughout instead of barring.
Hairy	ha	Recessive. This is the only gene that has been reported (as of 1990) to influence feather structure in turkeys. Causes unusually hairy-looking feathers. Causes an absence of normal webbing (caused by the separation of the feather barbs from each other).
Dermal melanosis	m	Recessive. First seen in Broad-Breasted Bronze turkeys. Characterized by blue-black skin. Expresses by 12 weeks of age. Strongly influenced by sunlight.
Naked	na	Recessive. Some feathering of the wings is present. Affected birds often have deformed legs and feet.
Red	r	Recessive. This is the gene for red plumage found in Bourbon Red. It results in a reddish-brown coloration in the day-old poult and in the feathers of the adult. The 'bronze-red' is an heterozygous fowl.
Dominant slate	d or D	Incompletely dominant. This gene reduces the black pigmentation to a uniform slate-blue throughout the plumage. It has little effect on red pigmentation. The homozygote has slate-blue plumage with barring on wing and tail.
Recessive slate	sl	Recessive. Gives a lilac plumage with nearly white flight feathers and unpencilled tail in homozygous state.
Palm	p	Recessive. Gives the plumage color of the Royal Palm variety. Adult feathing is primarily silvery-white with iridescent black bars and white tips.
Spotting	sp	Recessive. Sometimes called 'Nebraskan'. White feathers with black pigment dispersed in all feathers.
Faded bronze	fb	Recessive. Influences both plumage color and the central nervous system. Day-old poults demonstrate abnormally slow movements of the head and poorly directed pecking. In older fowl the bronze pattern has a reddish tinge and feathring is characteristiclly rough in appearance with feathers broken and missing. Little or no mating behavior.