牛AGPAT6基因遗传特征与奶牛产奶性能相关性研究

Association Study on AGPAT6 Intron3 Polymorphism and Milk Performance of Dairy Cattle

【目的】研究牛AGPAT6基因的遗传多态及其对奶牛产奶性能的影响,以期找到可用的分子标记,为奶牛的分子育种提供依据。【方法】利用PCR-RFLPs方法分析了3个不同品系荷斯坦牛AGPAT6基因第3内含子PstI等7种酶切多态性,分析了2个多态位点对3个品系奶牛产奶量、乳脂率、乳蛋白率及乳中体细胞评分的影响。【结果】牛AGPAT6基因第3内含子的PstI-RFLPs和BanI-RFLPs普遍存在于中国荷斯坦、澳洲荷斯坦和加拿大荷斯坦3个试验群体。PstI-RFLPs和BanI-RFLPs与荷斯坦牛的乳脂率呈显著的相关(P<0.05);PstI-RFLPs与荷斯坦牛的体细胞评分呈显著的相关(P<0.05);BanI-RFLPs与荷斯坦牛的305d产奶成年当量呈显著的相关(P<0.05)。【结论】牛AGPAT6基因第3内含子的PstI酶切位点突变,等位基因B为乳脂率和体细胞评分的优势等位基因。BanI酶切位点突变,等位基因D为乳脂率的优势等位基因;等位基因C为产奶量的优势等位基因。

[ Objective ] Association between the polymorphism of AGPAT6 gene and the milk performance of dairy cattle was studied to search for applicable molecular markers in dairy breeding. [Method] PCR-RFLPs method was used for polymorphism identification in cloned intron3 of AGPAT6. Genotypic effects of AGPAT6 intron3 on milk yield, milk fat percentage, milk protein percentage and somatic cell score （SCS） were analyzed. [Result] A PstI-RFLP and a BanI-RFLP were detected in intron3 of AGPAT6 and were common in all the detected populations. The PstI-RFLP and BanI-RFLP were significantly related with milk fat percentage （P〈0.05）. The PstI-RFLP was in significant relation with SCS （P〈0.05）. The BanI -RFLP was in significant relation with 305 d matured equivalency of Holstein（P〈0.05）.[Conclusion ]The B allele of PstI-RFLP was a favorable allele of milk fat percentage and SCS for Holstein. The D allele of BanI -RFLP was a favorable allele of milk fat percentage and the C allele of BanI -RFLP was a favorable allele of 305 d matured equivalency for Holstein.