版纳小耳猪近交系5家系35个微卫星座位的遗传分析

利用35个微卫星座位对版纳小耳猪近交系5个家系进行了遗传检测。统计各家系的等位基因组成，计算各家系的平均基因纯合率，利用基因频率计算出各家系的平均杂合度及品系间的遗传距离，并进行系统聚类。结果表明各家系的平均基因纯合度均较高，其151家系达到88.79％；PIC（多态信息含量）和平均杂合度均较普通商品猪低；各家系等位基因组成差别较大；各家系间亲缘关系与其近交过程一致，据此认为版纳小耳猪近交系5家系均具有较高的近交程度；其基因多态性和遗传多样性较普通商品猪低；各家系均已构成独立遗传群体。

Genetic Analysis of 35 Microsatellite Loci in 5 Lineages of Xishuangbanna Miniature Pig Inbred Line

The polymorphism of 35 microsatellites in 5 lineages of Xishuangbanna small-ear miniature pig inbred line (XMI) was analysed. Nmuber of alleles of each lineage was counted, and rates of homozygote for 35 microsatellite loci in 5 lineages were calculated. According to gene frequencies of 35 microsatellites polymorphism information content (PIC) and mean heterozygosity were calculated for each lineage, and genetic distances between these lineage were estimated. The dendrograms were obtained based on genetic distances. The results suggest that rates of homozygote in these lineage are all high, and that is the highest in lineage 151. The results also suggest that polymorphism information content and mean heterozygosity in all the lineages are low. Composition of alleles of each lineage was quite different and the genetic relationship between lineages accorded with the process of inbred line. So it is suggested that the inbreeding degree of 5 lineages of XMI are all high, and the richness of genetic diversity is lower than general commercial pig breeds. It also shows each lineage has been different groups with individual genes.