Abstract:

【Objective】 To investigate the pattern of genetic variation of three inbred families of Wuzhishan Miniature pig (WZSP) from the 13th to the 18th generations. 【Method】 Fourteen autosome microsatellite DNA markers were used to estimate their genetic heterozygosity (H), polymorphic information content (PIC) and number of alleles (N). 【Result】 The results showed that the average N , H, PIC in the pooled samples of familiesⅠ F14-16, ⅡF15-18, Ⅲ F14-17 were 2 , 0.40, 0.26; 1.92, 0.32, 0.26, 2.17, 0.44 and 0.32, respectively. The 7 of 14 microsatellites had reached the homozygosis completely in families Ⅱat 18th. 【Conclusion】 The results suggested that the average N is decreasing and the genetic homozygosity is increasing with the improving inbred generation of WZSP. The differentiation coefficient is 0.07 between three inbreed families respectively. The highest level of genetic homozygosity is in families Ⅱat 18th, but genetic variation is a little difference between inbreeding pig and mice. However, this study revealed the pattern of genetic variation at microsatellite loci in the 3 inbred families of WZSP with one of the most important findings to be the high level of unexpected heterozygosity at some loci, e.g. Sw874 and Sw936 that could be part of the unique genetics of three families. A hypothesis is that certain functional genes linked with such microsatellite loci may be involved in the maintenance of viability of these inbred families of WZSP remains for further investigation.

Key words: Wuzhishan Miniature pig, inbred family, microsatellite, heterozygosity