Genetic Variation of Peptidase and Pyrophosphatase in the Chicken

Differences in electrophoretic mobilities of two chicken liver, kidney, and spleen enzymes have been demonstrated. A peptidase cleaving the dipeptide L-leucyl-alanine was found to be under the control of a single locus, Pep-1, in crosses between two breeds of chicken, White Leghorn (WL) and Rhode Island Red (RIR). Three alleles, a, b, and c were segregating in the WL breed but only two of these, a and c, seemed to be present in the RIR stock. The other enzyme investigated here was pyrophosphatase, and was shown to be under the control of one locus, Pyp, with two alleles, a and b. The two alleles had similar frequencies in the RIR breed, whereas in the WL breed, the a allele was more frequent.