Chu M X, Mu Y L, Fang L, Ye S C, Sun S H
Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Anim Biotechnol. 2007;18(1):65-73. doi: 10.1080/10495390601090950.
DNA polymorphism of the ovine prolactin receptor gene (PRLR) was investigated and used to study its effect on litter size in sheep. By means of PRLR gene sequence homology between sheep and human, three primer pairs were designed for polymerase chain reaction (PCR) amplification within intron 1 and exon 10 of the PRLR gene in sheep. In these parts of the gene the single nucleotide polymorphisms were detected by PCR-single strand conformation polymorphism (SSCP) in 314 Small Tail Han ewes. These poly-morphisms were used to study the associations with litter size. The results indicated that there were three genotypes (AA, AB and BB) detected by three primer pairs. For three primer pairs the frequency of allele A was 0.96, 0.79, 0.68; and the frequency of allele B was 0.04, 0.21, 0.32, respectively. The frequency of genotype AA was 0.93, 0.62, 0.51; the frequency of genotype AB was 0.06, 0.34, 0.34; the frequency of genotype BB was 0.01, 0.04, 0.15, respectively. The Small Tail Han ewes with genotype BB or AB had 0.64-0.76 or 0.44-0.54 more lambs than those with genotype AA, respectively. These results preliminarily showed that the prolactin receptor locus is either a major gene that influences the prolificacy in Small Tail Han sheep or is in close linkage with such a gene.
对绵羊催乳素受体基因（PRLR）的DNA多态性进行了研究，并用于研究其对绵羊产羔数的影响。通过绵羊与人类PRLR基因序列的同源性，设计了3对引物，用于绵羊PRLR基因第1内含子和第10外显子的聚合酶链反应（PCR）扩增。在314只小尾寒羊中，通过PCR-单链构象多态性（SSCP）检测该基因这些区域的单核苷酸多态性。利用这些多态性研究其与产羔数的关联。结果表明，3对引物检测到3种基因型（AA、AB和BB）。对于3对引物，等位基因A的频率分别为0.96、0.79、0.68；等位基因B的频率分别为0.04、0.21、0.32。基因型AA的频率分别为0.93、0.62、0.51；基因型AB的频率分别为0.06、0.34、0.34；基因型BB的频率分别为0.01、0.04、0.15。基因型为BB或AB的小尾寒羊分别比基因型为AA的多产0.64 - 0.76只或0.44 - 0.54只羔羊。这些结果初步表明，催乳素受体位点要么是影响小尾寒羊多产性的主基因，要么与这样一个基因紧密连锁。
