| PIGEON COLOUR GENETICS part 1 BASIC COLOURS. I would Like to Thank Mr David. L. Darbyshire for the wonderful article on Pigeon Genetics. Before discussing the actual colours, we must first explain the inheritance of the three basic colours, Ash Red, Blue and Brown. All pigeons have to be one of these basic colours, even though, due to modifiers, these colours may be masked, or the colour altered. The genes for basic colour are located on the same chromosome as the genes which determine the sex of the pigeon, and are therfore linked to sex. Hence the term, Sex Linked. A cock has two genes (a pair) on his sex chromosomes, which can influence colour. These two genes can be identical, so in this case would always transmit the same colour to the egg. Thus; this cock would be said to be HOMOZYGOUS (pure) for his basic colour. A cock HETEROZYGOUS (impure) for basic colour, would have two different basic colour genes on his sex chromosomes, and thus could transmit eithe of these two colours via his sperm, to the egg. Hens have only one basic colour influencing gene on their sex chromosome, and are said to be HEMIZYGOUS for basic colour. Hens therefore, are always pure for the basic colour which is seen. When discussing basic colour, we mean any pattern in that colour, as patterns are inherited separately to colour, and will be discussed later. The three basic pigeon colours in order of dominance are :- Ash Red symbolized BA Blue symbolized B+ Brown symbolized b Having two genes for colour, cock would be symbolized as follows :- Homozygous (pure) Ash Red cock; BA BA pure for Ash Red Heterozygous (impure) Ash Red cock BA B+ heterozygous for blue or BA b heterozygous for brown As a Blue Cock cannot carry Ash Red because of Ash Red's dominance to Blue, we can only have the following. Homozygous Blue Cock B+ B+ Pure for Blue Heterozygous Blue Cock B+ b Heterozygous for Brown Brown being the lowest of the Three in the scale of dominance, Cocks are always pure for Brown Therefore symbolized as b b. Having only one Gene capable of transmitting colour to there offspring, Hens are Symbolized as follows :- Ash Red Hen BA - Blue Hen B+ - Brown Hen b - I Have used the - Symbol to denote the lack of a second basic colour influencing gene in Hens. |