五个鸡群中催乳素基因密码子使用频率与产蛋量的关系分析

通过鸡催乳素基因编码区基因扫描,发现3个SNP位点,分别是外显子2的C1607T、外显子5的C5749T和T5821C,3个SNP均没有改变氨基酸的编码.同时发现不同的单倍型间存在不同的密码子使用频率.对5个鸡群共370只鸡进行SSCP的基因型检测,共发现7种单倍型,结合44周龄产蛋量分析,发现不同单倍型的平均产蛋量存在显著性差异.结合密码子使用频率分析,发现使用高频密码子的单倍型个体产蛋量相对高.通过酶联免疫方法检测催乳素表达量,结果显示,使用高频密码子的个体,激素水平较高,其中使用2个高频密码子的单倍型个体和使用1.5个密码子的单倍型个体之间存在极显著差异.研究结果表明,密码子使用频率与产蛋量在一定的范围内呈现正相关趋势.

Analysis of The Relationship Between Codon Frequency of Prolactin Gene and Laying Performance in Five Chicken Breeds

After analyzing the coding sequence (CDS) of chicken prolactin gene by DNA sequencing, one point mutation of C1607T in exon2 and two mutations of C5749T and T5821C in exon5 were discovered. Although none of the mutations changes amino acid encoded, they have different codon frequencies in the five populations. The three mutations in 370 individuals of the five populations by single-strand conformation polymorphism (SSCP) were screened, and seven haplotypes in the CDS of prolactin were discovered. Moreover, the seven haplotypes show different high frequency value, which was defined by the number of high frequency codon of the haplotype. Analyzing the laying performance of the five breeds, the positive correlation between the laying performance and high frequencies value wea found. After detecting the expression of the prolactin by enzyme linked immunosorbent assay (ELISA), it was found that the higher number of high frequency condon will lead to the more quantity of prolactin. The results demonstrate that the codon frequency is a factor which influence the laying performance, and synonymous mutation might influence phenotype by changing codon frequency.