绵羊BMPR-IB基因多态性与其产羔数的相关研究

本研究以绵羊BMPR -IB基因为候选基因 ,以湖羊、中国美利奴单胎品系、中国美利奴肉用和毛用多胎品系为研究对象 ,通过PCR -RFLP检测该基因的单核苷酸多态性 (SNP)位点 ,同时研究该基因对绵羊产羔数的影响。研究发现 ,在BMPR -IB基因序列第 74 6碱基处有一个A /GSNP位点 ,结果在不同品系羊中产生 3种基因型 (BB、B +和 ++)。基因型频率在各品种 (系 )间差异极显著 (P <0 .0 0 1) ,在湖羊中以BB基因型为主 ,在中国美利奴单胎品系中以 ++基因型为主 ,而在中国美利奴肉用和毛用多胎品系中以B +基因型为主。BB和B +基因型的母羊产羔数明显较 ++基因型的母羊多。BMPR -IB基因型在绵羊各品系间的分布和各种基因型绵羊的实际产羔情况两方面的研究结果强烈表明BMPR -IB为影响绵羊的产羔数的主效基因 ,可以用于对绵羊产羔数的选择。

The polymorphism of BMP - IB gene associated with litter size in sheep

The current study was designed to detect SNPs within BMPR-IB gene and investigate the effect of BMPR-IB gene on sheep litter size. Four sheep lines, HU-Yang, Chinese Merino monotocous, Chinese Merino multiparous for wool production and Chinese Merino multiparous for mutton production, were used in this study. Litter sizes were recorded for each ewe in the four lines. Primers for BMPR-IB was designed from database sheep sequence and polymorphisms were detected by PCR-RFLP method. The results showed that there was an A / G SNP among the four lines at base 746. The genotype (BB, B+ and ++) frequencies were significantly different among the lines (P<0.001), with BB genotype primarily existing in HU-Yang, ++ genotype in Chinese Merino monotocous line, and B+ genotype in Chinnese Merino multiparous lines. The BB and B+ ewes had significant higher litter sizes than ++ ewes. These results intensively indicated that BMPR-IB is a major gene to affect litter size in sheep , and could be used as the molecular genetic marker to select litter size in sheep.