A growing body of evidence suggests that mutation rates exhibit intra-species specific variation. We estimated genome-wide loss of heterozygosity (LOH), gross chromosomal changes, and single nucleotide mutation rates to determine intra-species specific differences in hybrid and homozygous strains of Saccharomyces cerevisiae. The mutation accumulation lines of the S. cerevisiae hybrid backgrounds - S288c/YJM789 (S/Y) and S288c/RM11-1a (S/R) were analyzed along with the homozygous diploids RM11, S288c, and YJM145. LOH was extensive in both S/Y and S/R hybrid backgrounds. The S/Y background also showed longer LOH tracts, gross chromosomal changes, and aneuploidy. Short copy number aberrations were observed in the S/R background. LOH data from the S/Y and S/R hybrids were used to construct a LOH map for S288c to identify hotspots. Further, we observe up to a sixfold difference in single nucleotide mutation rates among the S. cerevisiae S/Y and S/R genetic backgrounds. Our results demonstrate LOH is common during mitotic divisions in S. cerevisiae hybrids and also highlight genome-wide differences in LOH patterns and rates of single nucleotide mutations between commonly used S. cerevisiae hybrid genetic backgrounds.

越来越多的证据表明，突变率表现出种内特异性变异。我们估计杂合度（LOH），总染色体变化和单核苷酸突变率的全基因组损失，以确定酿酒酵母的杂种和纯合菌株的种内特异性差异。酿酒酵母的突变积累系杂种背景-分析了S288c / YJM789（S / Y）和S288c / RM11-1a（S / R）以及纯合二倍体RM11，S288c和YJM145。LOH在S / Y和S / R混合背景中都有广泛的应用。S / Y背景还显示出更长的LOH区域，总体染色体变化和非整倍性。在S / R背景中观察到短拷贝数畸变。来自S / Y和S / R杂种的LOH数据用于构建S288c的LOH图，以识别热点。此外，我们观察到酿酒酵母S / Y和S / R遗传背景之间的单核苷酸突变率差异高达六倍。我们的结果表明，LOH在酿酒酵母的有丝分裂分裂中很常见杂种，也突出了常用酿酒酵母杂种遗传背景之间LOH模式和单核苷酸突变率的全基因组差异。