Y-chromosome diversity in dairy bulls of Tamil Nadu

The Y-chromosome specific microsatellite studies are of particular interest as they could reveal the paternal lineage and domestication pattern among the population distributed over geographical area. As few bulls are used against large number of cows using artificial insemination approach, it is necessary to study the Y-chromosome microsatellite markers to understand the Y-chromosome diversity, paternal lineage and molecular variation among population. The present study included 431 bulls comprising Bos taurus, Bos indicus and crossbreds from various frozen semen stations of Tamil Nadu. The microsatellites loci viz. UMN0103, UMN0307, BM861, UMN0504, INRA189, INRA124, DDX3Y and UMN2008 were screened. The overall mean number of different alleles, number of effective alleles, Shannon's information index, diversity and unbiased diversity were 2.18 +/- 0.16, 1.37 +/- 0.06, 0.35 +/- 0.04, 0.20 +/- 0.02 and 0.21 +/- 0.02 respectively. The analysis of molecular variance revealed that the variation within populations accounted for 66 per cent of total variation.