中国4个牛品种LHX4基因的多态性及遗传效应

Polymorphisms and Genetic Effects of LHX4 Gene in Four Chinese Cattle Breeds

利用PCR-SSCP和DNA测序技术,对秦川牛、南阳牛、郏县红牛和中国荷斯坦牛(共计817个个体)的LHX4基因外显子5及其两侧部分内含子序列进行多态性分析,并结合南阳牛的生长指标,分析不同基因型的遗传效应。新发现3处单核苷酸突变位点,分别是NW_001493443:g.42757G>A、NW_001493443:g.42768A>G和NW_001493443:g.42917T>C,并因此形成AA、AB和BB 3种基因型。4个牛群体中,AA基因型的频率分别为0.766 2、0.771 70、.723 4和0.891 3。群体间的χ2检验结果揭示,不同牛品种的基因型频率差异不显著(P>0.05)。南阳牛群体中不同基因型个体与生长指标间的相关性分析结果显示,AA基因型个体的6月龄体质量显著大于其他基因型个体(P<0.05),暗示该位点有可能作为南阳牛生长性状辅助选择的标记之一。

PCR-SSCP and DNA sequencing methods were employed to screen the genetic variation of the exon 5 and it＇s flanking of LHX4 gene in 817 Chinese indigenous cattle（QC,NY,JX and CH）.The Associations of different genotypes with some of growth and development traits were also analysed in NY cattle breed.The results revealed three novel mutations： NW_001493443：g.42757GA,NW_001493443：g.42768AG and NW_001493443：g.42917TC.There were three genotypes： AA,AB and BB.The AA genotypic frequencies in the four populations are 0.766 2,0.771 7,0.723 4 and 0.891 3 respectively.Distributions of genotypic frequencies in these Chinese cattle breeds at this locus were not found to be significantly different among populations based by a χ2 test（P〉0.05）.The association analysis of different genotypes with some of the growth and development traits in NY cattle showed that the individuals with genotype AA had a larger mass weight at six months than the individuals with other genotypes（P〈0.05）.It implied that the locus of LHX4 gene exon 5 and its flanking might be a potential useful genetic marker in bovine breeding and genetics for molecular-assisted selection.