Chromosomes, hemoglobins, and transferrins of Iranian domestic sheep.

Abstract

Twelve breeds of Iranian domestic sheep were cytogenetically analyzed. The diploid chromosome number of 2n = 54 is identical to that of most breeds of domestic sheep, which is comprised of 3 pairs of metacentric and 23 pairs of acrocentric autosomes. The sex chromosomes consist of a large acrocentric X and a small bi-armed Y. Hemoglobin analysis by isoelectric focusing for these 12 breeds resulted in the identification of 2 protein fractions: Hb AB and B. The A allele was observed in 7 percent of the 506 sheep sampled, in 6 of the 12 breeds, and then only in the heterozygous form. Transferrins were analyzed by starch-gel electrophoresis and comparisons made between breeds. Nine alleles, pooled frequency of occurrence in descending order, B, C, D, A, M, E, G, P, and I were identified and resulted in 19 phenotypes. Tfs A, B, C, and D were observed in all breeds, whereas I was found in 2,G in 1, M in 8, E in 6, and P in 2. Significant differences in allelic occurrence of Tfs A, B, C, and D were observed in seven breeds.