微卫星标记对资源猪群的遗传分析和连锁图谱构建

在猪数量性状位点的定位研究中,标记的使用和图谱的构建是很重要的。本研究从猪的第4、6、7、8和13染色体上选取39个微卫星标记,在来源于约克夏和梅山214头猪组成的资源群中,分析了遗传特征并构建了图谱。研究表明,平均等位基因数、平均观察杂合度(Ho)和平均多态信息含量(PIC)在F1和F2代中分别为:3.2,0.528,0.463和3.2,0.496,0.447。结果表明大多数微卫星标记位点表现为中高度杂合性。在资源群体中,平均有信息减数分裂数是217.4(44-316),而各染色体上两性平均图谱的长度分别是:172.3cM(SSC4),168.7cM(SSC6),191.7cM(SSC7),197.3cM(SSC8),178.3cM(SSC13)。与USDA-MARC的参考图谱相比,标记位点的顺序相同,但长度均较长。雌雄两性图谱相比,第4和第6染色体上雌性图谱长于雄性图谱;而在另外3条染色体上,则雄性图谱长于雌性图谱。结果显示了标记位点在资源猪群的遗传特征和遗传关系,其连锁图谱可用于今后的QTL定位。

Genetic Analysis and Linkage Mapping in a Resource Pig Population Using Microsatellite Markers

The use of markers and linkage map construction are important for QTL mapping in pigs. In this article, the genetic characteristics were studied and the linkage map was constructed in a pig resource population including 214 individuals by typing 39 microsatellite marker loci on Sus scrofa chromosomes, SSC4, SSC6, SSC7, SSC8, and SSC13. Results indicated that the average allele number, the average observed heterozygosity (H(0)), and the average polymorphism information content (PIC) in F(1) and F(2) population were 3.2, 0.528, 0.463 and 3.2, 0.496, 0.447, respectively. In the pig resource population, the average informative meiosis (IM) was 217.4 (44-316), and the average linkage map length between the two sexes on the five chromosomes were 172.3 cM (SSC4), 168.7 cM (SSC6), 191.7 cM (SSC7), 197.3 cM (SSC8), and 178.3 cM (SSC13). The orders of microsatellite marker loci in the linkage maps were identical to, but the length was greater than, those of USDA-MARC reference map. The results of this research showed the genetic relationship and genetic characteristics of the microsatellite markers in the pig resource family population, and the linkage map could be used to for QTL mapping in the subsequent study.