Abstract

The study was conducted to determine the genetic variants of κ-casein and β-lactoglobulin genes in native cattle. DNA was extracted from blood samples (n = 80) collected from Babuganj, Barishal followed by PCR with gene-specific primers. Genotyping was done by RFLP with HindIII, and HaeIII restriction enzymes. Allelic and genotypic frequencies, genetic diversity, heterozygosity and Hardy–Weinberg equilibrium were estimated using the Popgen32 software. A total 80 samples were genotyped and three genotypes, namely AA, AB and BB, were detected for both the genes. In case of κ-casein gene, higher frequency was observed for AA genotype (0.73) followed by AB (0.23) and BB (0.04) genotype. A allele (0.84) was found to dominate over B allele (0.16). For β-lactoglobulin gene, BB genotype (0.66) was found more frequently than AB (0.18) and AA (0.16) genotypes. Highest frequency was found for B (0.75) followed by A (0.25) allele. The average genetic diversity (He) was 0.38. The result indicated differences between observed (Ho) and expected (He) heterozygosity and it was out of equilibrium genetics, assumed that selection pressure was in population. To the best of our knowledge, this is the first reported study on κ-casein and β-lactoglobulin gene variants analysis in cattle in Bangladesh.

摘要

该研究旨在确定天然牛中κ-酪蛋白和β-乳球蛋白基因的遗传变异。从从 Babuganj, Barishal 收集的血液样本 ( n  = 80) 中提取 DNA，然后用基因特异性引物进行 PCR。RFLP 使用HindIII和HaeIII限制性内切酶进行基因分型。使用 Popgen32 软件估计等位基因和基因型频率、遗传多样性、杂合性和 Hardy-Weinberg 平衡。共对80个样本进行了基因分型，检测到这两个基因的三种基因型，即AA、AB和BB。如果是κ-酪蛋白基因，AA基因型（0.73）的频率较高，其次是AB（0.23）和BB（0.04）基因型。发现等位基因 (0.84) 优于 B 等位基因 (0.16)。对于β-乳球蛋白基因，BB基因型（0.66）比AB（0.18）和AA（0.16）基因型更常见。B (0.75) 的频率最高，其次是 A (0.25) 等位基因。平均遗传多样性（He）为0.38。结果表明观察到的（Ho）和预期的（He）杂合性之间存在差异，并且它不平衡遗传，假设选择压力存在于群体中。据我们所知，这是首次报道的关于孟加拉国牛的κ-酪蛋白和β-乳球蛋白基因变异分析的研究。