石歧杂鸡催乳素基因外显子4变异与产蛋就巢性状的关联分析

利用PCR-SSCP技术和测序技术对催乳素（prolactin，PRL）基因外显子4进行SNP检测，并分析了该基因与石歧杂鸡产蛋、就巢性状的相关性。结果表明，PRL基因外显子4存在1个多态性位点，该位点在6017位点发生G→A的碱基突变，产生了AA、AB和BB 3种基因型，AA基因型为优势基因型，等位基因A为优势等位基因，该突变未导致氨基酸的变异；该位点的变异与开产日龄、首次就巢日龄呈现一定的显著差异趋势，BB基因型开产日龄、首次就巢日龄都晚于AA和AB基因型。

SNP Detection of Exon 4 of Prolactin Gene and its Associations with Egg-laying and Broodiness Traits in Shiqiza Chicken

Exon 4 of prolactin gene were detected by PCR-SSCP and the DNA fragments were sequenced．The correlation analysis between the polymorphism of the exon 4 and egg-laying and broodiness traits were carried out respectively．The results indicated that there were one polymorphic sites in exon 4 ．A G→A mutation at the position of the 6017 bp was found，which resulted in 3 genotypes(AA，AB and BB)，but the mutation did not lead to changes in amino acid. The frequencies of genotype AA and allele A were the highest．The least square analysis showed that the first broodiness day and age at 1st egg of BB type chickens was later than AA and AB types chickens，The locus of variation showed a definite trend in the age at 1st egg and the first broodiness day.