Evaluation of genetic variability and genetic distances between eight chicken lines using microsatellite markers

The genetic variability and divergence of eight chicken lines were evaluated using nine microsatellite markers. The chicken lines included three White Leghorn hybrids, three Finnish Landrace lines, a Rhode Island Red line, and a broiler hybrid line. All the microsatellite loci were found to be polymorphic, the number of alleles varying from 4 to 13 per locus and 1 to 10 per line, respectively. Observed heterozygosities ranged from 0.00 to 0.91. The highest (0.67) and lowest (0.29) mean heterozygosity per line was observed in the broiler and in White Leghorn of Mäkelä, respectively. Three of the microsatellite loci deviated from the Hardy-Weinberg equilibrium in some populations. F statistics indicated clearly the subdivision of the total population into different lines. The genetic distances confirmed the classification of Finnish Landraces into different lines. A phylogenetic consensus tree was constructed from resampled data (1,000 times) using the neighbor-joining method. According to the phylogenetic tree, the lines were grouped into three clusters, in which the White Leghorns formed one group, two Landraces a second group, and a Landrace, the Rhode Island Red, and the broiler lines a third group. Allele distribution at the loci does not support either the stepwise or the infinite alleles mutation model, but the distribution pattern was quite irregular at different loci.