Application of microsatellite analysis to group chicken according to their genetic similarity

Dedicated to Professor Dr. Peter Glodek on the occasion ofhis 65"' birthday Summary When estimating genetic variability of groups of local chicken from Nigeria we had to deal with the problem that the groups could not be regarded as distinct breeds or strains. The original sample groups obviously just represent individuals sampled in the same geographical region. The aim was to arrange these chicken in new groups according to their genetic similarity. Therefore 60 chicken from Nigeria and 10 Dahlem Reds (RIR) were genotyped at 20 microsatellite loci. In order to build up new groups "allele sharing" was calculated as the proportion of shared alleles beUveen each pair of individuals and was used to construct a dendrogram of all individuals including Dahlem Reds as a reference group which represents a well defined line. All Dahlem Reds clustered in this dendrogram indicating that this is an adequate approach to group individuals according to their common genetic make-up. The Nigerian chicken were arranged in 7 new groups. CHORD genetic distances between these new groups ranged from 0.07 to 0.27 and were higher than the values revealed by the original local sample groups (0.05 - 0.16).