Chu M X, Wang X C, Jin M, Di R, Chen H Q, Zhu G Q, Fang L, Ma Y H, Li K
The Key Laboratory of Domestic Animal Genetic Resources and Germplasm Innovation of CAAS, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
J Anim Breed Genet. 2009 Feb;126(1):63-8. doi: 10.1111/j.1439-0388.2008.00763.x.
A single nucleotide polymorphism of 5' flanking region of the prolactin gene was investigated in both high prolificacy breeds (Small Tail Han and Hu sheep) and low prolificacy breeds (Dorset and Suffolk sheep) using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP). The results indicated that two genotypes (AA and AB) were detected in Small Tail Han sheep (n = 239), only one genotype (AA) was detected in Hu (n = 40), Dorset (n = 50) and Suffolk sheep (n = 39). The mutant homozygous genotype (BB) was not detected in four sheep breeds. In Small Tail Han sheep (n = 239), the frequency of genotypes AA and AB was 0.91 and 0.09, the frequency of the A and B alleles was 0.95 and 0.05, respectively. The fitness tests showed that the Small Tail Han sheep population was in Hardy-Weinberg equilibrium. Sequencing revealed a mutation (G-->T) at the position 63 bp of the 5' flanking region of prolactin gene in AB genotype compared with AA genotype in Small Tail Han sheep. The Small Tail Han ewes with AB genotype had 0.83 (p < 0.05) lambs more than those with AA genotype. These results preliminarily showed that the prolactin locus is either a major gene that influences the high prolificacy in Small Tail Han sheep or is in close linkage with such a gene.
采用聚合酶链反应（PCR）-单链构象多态性（SSCP）技术，对高繁殖力品种（小尾寒羊和湖羊）和低繁殖力品种（多赛特羊和萨福克羊）的催乳素基因5'侧翼区单核苷酸多态性进行了研究。结果表明，在小尾寒羊（n = 239）中检测到两种基因型（AA和AB），在湖羊（n = 40）、多赛特羊（n = 50）和萨福克羊（n = 39）中仅检测到一种基因型（AA）。在四个绵羊品种中均未检测到突变纯合基因型（BB）。在小尾寒羊（n = 239）中，基因型AA和AB的频率分别为0.91和0.09，A和B等位基因的频率分别为0.95和0.05。适合性检验表明，小尾寒羊群体处于哈迪-温伯格平衡状态。测序结果显示，与小尾寒羊AA基因型相比，AB基因型催乳素基因5'侧翼区63 bp处发生了一个突变（G→T）。AB基因型的小尾寒羊母羊比AA基因型的母羊多产0.83只羔羊（p < 0.05）。这些结果初步表明，催乳素基因座要么是影响小尾寒羊高繁殖力的主基因，要么与这样一个基因紧密连锁。
