Studies of Genetic Distance, Gene and Genotypic Frequencies of Hemoglobin Types of West African Dwarf and Yankassa Sheep

Abstract

Hemoglobin (Hb) alleles, genotype and their frequencies were studied in 50 West African Dwarf (WAD) and 50 Yankasa sheep. Blood samples were collected from the animals and analysed, hemoglobin (Hb) type were determined by cellulose acetate electrophoresis. The resultant data were subjected to statistical analyses. The gene frequencies estimated in each allele of the population and were tested using Hardy-Weinberg equilibrium. The genetic distance was thereafter estimated according to Bodmer and Cavalli-Sforza method. The frequencies of Hb(A) and Hb(B) in WAD sheep were 0.35 and 0.65 and genotype frequencies were HbAA (0.34), HbAB (0.00) and HbBB (0.66). The corresponding values in Yankassa sheep were 0.75 and 0.25, 0.70, 0.10 and 0.20, respectively. The distribution of the haemoglobin genotypes was tested using Chi-square analysis. The genetic distance at the haemoglobin locus between WAD and Yankassa sheep was estimated and was found to be 0.16, which shows that within the limit of these small populations sampled, there is a similarity of alleles at the locus. Sampling larger number animals in different breeds of sheep will allow for a better genetic studies and marker-assisted selections in sheep improvement programs.

Keywords: Genetic Distance, hemoglobin, Sheep, WAD, Yankassa.