Background/Aim: The number of vertebrae in swine varies from 19 to 23 and is associated with body size. Nuclear receptor subfamily 6 group A member 1 (NR6A1) is considered a strong candidate for affecting the number of vertebrae in swine. Wild boars, which uniformly have 19 vertebrae, have the wild type allele while multi-vertebrae European commercial pigs have the mutated allele. Our aim was to confirm the factor of the miniaturization. Materials and Methods: We examined vertebrae number and NR6A1 polymorphism in the Microminipig and three domestic breeds that vary in body size. Results: The Microminipig had 19 or less vertebrae and a wild type NR6A1 genotype. Three domestic breeds had more than 21 vertebrae while the largest vertebrae number was observed in multi-vertebrae-fixed Large White. Heterozygous genotypes were observed in the middle-sized indigenous pig while homozygous NR6A1 mutations were observed in European commercial breeds. Conclusion: NR6A1 could be a useful index for both miniaturizing and increasing pig body size.

中文翻译：

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NR6A1 等位基因频率作为猪体型小型化和增加的指标


背景/目的：猪的椎骨数量从 19 到 23 不等，并且与体型相关。核受体亚家族 6 A 组成员 1 (NR6A1) 被认为是影响猪椎骨数量的有力候选者。野猪统一有 19 块椎骨，具有野生型等位基因，而多椎骨的欧洲商品猪则具有突变等位基因。我们的目的是确认小型化的因素。材料和方法：我们检查了微型猪和三个体型不同的家养品种的椎骨数量和 NR6A1 多态性。结果：微型猪有 19 块或更少的椎骨，并且具有野生型 NR6A1 基因型。三个家养品种拥有超过 21 块椎骨，其中椎骨数量最多的是多椎骨固定的大白鲨。在中型本土猪中观察到杂合基因型，而在欧洲商业品种中观察到纯合 NR6A1 突变。结论：NR6A1可能是猪体型小型化和体型增大的有用指标。