Sypniewski Mateusz, Strabel Tomasz, Pszczola Marcin
Department of Genetics and Animal Breeding, Poznan University of Life Sciences, 60-637 Poznan, Poland.
Animals (Basel). 2021 Nov 6;11(11):3175. doi: 10.3390/ani11113175.
The genetic architecture of methane (CH) production remains largely unknown. We aimed to estimate its heritability and to perform genome-wide association studies (GWAS) for the identification of candidate genes associated with two phenotypes: CH in parts per million/day (CH ppm/d) and CH in grams/day (CH g/d). We studied 483 Polish Holstein-Friesian cows kept on two commercial farms in Poland. Measurements of CH and carbon dioxide (CO) concentrations exhaled by cows during milking were obtained using gas analyzers installed in the automated milking system on the farms. Genomic analyses were performed using a single-step BLUP approach. The percentage of genetic variance explained by SNPs was calculated for each SNP separately and then for the windows of neighbouring SNPs. The heritability of CH ppm/d ranged from 0 to 0.14, with an average of 0.085. The heritability of CH g/d ranged from 0.13 to 0.26, with an average of 0.22. The GWAS detected potential candidate SNPs on BTA 14 which explained ~0.9% of genetic variance for CH ppm/d and ~1% of genetic variance for CH g/d. All identified SNPs were located in the TRPS1 gene. We showed that methane traits are partially controlled by genes; however, the detected SNPs explained only a small part of genetic variation-implying that both CH ppm/d and CH g/d are highly polygenic traits.
甲烷（CH）产生的遗传结构在很大程度上仍然未知。我们旨在估计其遗传力，并进行全基因组关联研究（GWAS），以鉴定与两种表型相关的候选基因：百万分之一/天的CH（CH ppm/d）和克/天的CH（CH g/d）。我们研究了波兰两个商业农场饲养的483头波兰荷斯坦-弗里生奶牛。使用安装在农场自动挤奶系统中的气体分析仪，对奶牛挤奶期间呼出的CH和二氧化碳（CO）浓度进行了测量。使用单步BLUP方法进行基因组分析。分别计算每个SNP以及相邻SNP窗口所解释的遗传方差百分比。CH ppm/d的遗传力范围为0至0.14，平均为0.085。CH g/d的遗传力范围为0.13至0.26，平均为0.22。GWAS在BTA 14上检测到潜在的候选SNP，它们解释了CH ppm/d约0.9%的遗传方差和CH g/d约1%的遗传方差。所有鉴定出的SNP都位于TRPS1基因中。我们表明，甲烷性状部分受基因控制；然而，检测到的SNP仅解释了一小部分遗传变异，这意味着CH ppm/d和CH g/d都是高度多基因性状。
