Kolenda Magdalena, Sitkowska Beata
Department of Animal Biotechnology and Genetics, Faculty of Animal Breeding and Biology, UTP University of Science and Technology, 85-084 Bydgoszcz, Poland.
Animals (Basel). 2021 Feb 3;11(2):389. doi: 10.3390/ani11020389.
The aim of the present study was to evaluate the genotype and allele frequencies of 24 polymorphisms in casein alpha S1 (CSN1S1), casein alpha S2 (CSN1S2), beta-casein (CSN2), kappa-casein (CSN3), and progestagen-associated endometrial protein (PAEP) genes. The study included 1900 Polish Black and White Holstein-Friesian dairy cows that were subjected to genotyping via microarrays. A total of 24 SNPs (Single Nucleotide Polymorphisms) within tested genes were investigated. Two CSN1S1 SNPs were monomorphic, while allele CSN1S1_3*G in CSN1S1_3 SNP dominated with a frequency of 99.39%. Out of seven CSN2 SNPs, four were polymorphic; however, only for CSN2_3 all three genotypes were detected. Only three out of nine SNPs within CSN3 were monomorphic. Three PAEP SNPs were also found to be polymorphic with heterozygotes being most frequent. Hardy-Weinberg equilibrium (HWE) was observed for eight variants. It was shown that only CSN3_6 was not in HWE. The fact that many of investigated SNPs were monomorphic may suggest that in the past the reproduction program favored one of these genotypes. SNPs that are included in commercially available microarrays should be monitored in relation to changes in their frequencies. If a SNP has turned monomorphic, maybe it should be considered for removal from the microarray.
本研究的目的是评估酪蛋白α S1（CSN1S1）、酪蛋白α S2（CSN1S2）、β-酪蛋白（CSN2）、κ-酪蛋白（CSN3）和孕激素相关子宫内膜蛋白（PAEP）基因中24个多态性位点的基因型和等位基因频率。该研究纳入了1900头波兰黑白花荷斯坦奶牛，通过微阵列对其进行基因分型。共研究了测试基因内的24个单核苷酸多态性（SNP）。CSN1S1的两个SNP是单态的，而CSN1S1_3 SNP中的等位基因CSN1S1_3*G占主导，频率为99.39%。在CSN2的七个SNP中，四个是多态的；然而，仅在CSN2_3中检测到了所有三种基因型。CSN3的九个SNP中只有三个是单态的。还发现PAEP的三个SNP是多态的，杂合子最为常见。八个变异位点符合哈迪-温伯格平衡（HWE）。结果表明，只有CSN3_6不符合HWE。许多被研究的SNP是单态的这一事实可能表明，过去的繁殖计划有利于这些基因型中的一种。应监测商业可用微阵列中包含的SNP的频率变化。如果一个SNP变成了单态的，也许应该考虑将其从微阵列中移除。
