PCR-single-strand conformation polymorphism (PCR-SSCP) assay was used to diagnose the K232A substitution in the DGAT1 exon 8 Animals from three dairy cattle populations (212 Sanhe cattle,234 Chinese Holsteins and 200 Chinese Simmentals) were used to estimate allele frequencies and gene substitution effects on milk production traits. Another four populations (47 Luxi, 23 Jinnan, 37 Qinchuan and 39 Nanyang cattle) without production records were used to estimate allele frequencies only. The allele frequencies for the lysine-encoding variant (allele K) were 0.17,0. 33 and 0.04 in Sanhe,Holstein,Simmental cows respectively;and 0.72,0.39,0.46and 0.83 respectively in the other four populations. The average milk fat percentage in Sanhe cattle was associated (P=0.017) with the K232A substitution in DGAT1 gene,individuals with genotypes KK and KA had 0.80% and 0.41% higher average milk fat percentage than those with genotype AA.%利用单链构向多态性方法检测了牛DGAT1基因第8外元AA→GC碱基突变,分析了该突变在三河牛、中国荷斯坦奶牛和中国西门塔尔奶牛中等位基因的分布频率,以及该突变对这3个品种奶牛群体产奶量、乳脂和乳蛋白含量的影响,并分析了该突变在鲁西牛、晋南牛、秦川牛和南阳牛中等位基因分布频率.结果表明,编码赖氨酸的等位基因K在三河牛、中国荷斯坦牛和中国西门塔尔牛中的分布频率分别为0.17,0.33和0.04,在鲁西牛、晋南牛、秦川牛和南阳牛4个中国地方品种中的分布频率分别为0.72,0.39,0.46和0.83;K232A取代与三河牛的平均乳脂率相关(P=0.017),KK和KA基因型个体的平均乳脂率分别较AA基因型个体高0.80%和0.41%.
展开▼
