Genetic Variability and Relationships of Japanese Native Chickens Assessed by Means of Microsatellite Profiling Approach-Focusing on the Oh-Shamo (Japanese Large Game) and Its Related Breeds

Assessment of genetic relatedness of crossbred chicken populations using microsatellite markers

To measure genetic relatedness between populations, for breeding purposes, we analyzed 170 birds from six crossbred populations of three pure lines of White Leghorn chickens, using 14 microsatellite markers. All the microsatellites were polymorphic, with 2-6 alleles. The mean number of alleles per locus was 3.21. The effective number of alleles varied from 1.14 to 3.94. The observed heterozygosity varied from 0.133 to 1.00, with a mean of 0.748. The F (IS) values were mostly negative, with an average of -0.345. The mean F (ST) value was 0.056. The Nm values ranged from 1.91 to 42.17. The highest genetic identity was observed between IWI x IWK and IWK x IWI. The relation between any two groups of crosses was more than 85%. The results suggest that the crossbred populations were very closely related.

Microsatellite Marker Analysis for the Genetic Relationships Among Japanese Long-Tailed Chicken Breeds

The present study was conducted to evaluate the genetic diversity and relationships of 9 native Japanese long-tailed chicken breeds (Shoukoku, Koeyoshi, Kurokashiwa, Minohiki, Ohiki, Onagadori, Satsumadori, Toumaru, and Toutenkou) together with 2 commercial breeds (White Leghorn and White Plymouth Rock), using 40 polymorphic microsatellite markers covering 23 linkage groups. The 8 breeds mentioned, except for Shoukoku and 2 commercial breeds, were believed to be descendants derived from crossings of the ancestor of Shoukoku and some other breeds. Three to 14 alleles per locus were detected across all the breeds. The mean number of alleles per locus, the mean unbiased expected heterozygosity, and the mean polymorphic information content ranged from 2.60 (Minohiki) to 4.07 (Shoukoku), from 0.293 (Koeyoshi) to 0.545 (Satsumadori), and from 0.250 (Koeyoshi) to 0.478 (Satsumadori), respectively. The mean fixation coefficient of subpopulation within the total population of 9 Japanese long-tailed breeds showed that approximately 38% of the genetic variation was caused by breed differences and 62% was due to differences among individuals. Toumaru had the largest number of breed-specific alleles with relatively high (>20%) frequency. In the phylogenetic tree of 11 breeds constructed by the neighbor-joining method from modified Cavalli-Sforza chord genetic distance measure, White Leghorn and White Plymouth Rock clustered together apart from the Japanese breeds. Among the Japanese long-tailed breeds, Toumaru, Kurokashiwa, and Koeyoshi showed relatively far distance from the other breeds. The Ohiki, Onagadori, Shoukoku, and Toutenkou were grouped into the same branch. Minohiki and Satsumadori were also clustered together. Kurokashiwa was not genetically close to Shoukoku, differing from a traditional hypothsis. It was confirmed in the present study that the microsatellite is a suitable tool to evaluate genetic diversity and relationships in chicken breeds.