The number of teats is a morphological trait that influences the mothering ability of the sows and thus their reproduction performances. In this study, we carried out GWASs for the total number of teats and other 12 related parameters in 821 Italian Large White heavy pigs. All pigs were genotyped with the Illumina PorcineSNP60 BeadChip array. For four investigated parameters (total number of teats, the number of teats of the left line, the number of teats of the right line and the maximum number of teats comparing the two sides), significant markers were identified on SSC7, in the region of the vertnin (VRTN ) gene. Significant markers for the numbers of posterior teats and the absolute difference between anterior and posterior teat numbers were consistently identified on SSC6. The most significant SNP for these parameters was an intron variant in the TOX high mobility group box family member 3 (TOX3 ) gene. For the other four parameters (absolute difference between the two sides; anterior teats; the ratio between the posterior and the anterior number of teats; and the absence or the presence of extra teats) only suggestively significant markers were identified on several other chromosomes. This study further supported the role of the VRTN gene region in affecting the recorded variability of the number of teats in the Italian Large White pig population and identified a genomic region potentially affecting the biological mechanisms controlling the developmental programme of morphological features in pigs.

中文翻译：

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全基因组关联研究大白猪的奶头数量和奶头不对称模式。

奶头的数量是一种形态特征，会影响母猪的母体繁殖能力，进而影响母猪的繁殖性能。在这项研究中，我们对821头意大利大白重猪的乳头总数和其他12个相关参数进行了GWAS。用Illumina PorcineSNP60 BeadChip阵列对所有猪进行基因分型。对于四个调查参数（奶嘴总数，左行奶嘴数量，右行奶嘴数量以及将两侧进行比较的最大奶嘴数量），在SSC7区域中确定了重要标记在vertnin（VRTN）基因。在SSC6上一致地确定了后乳头数量的显着标记以及前后乳头数量之间的绝对差异。这些参数最重要的SNP是TOX高迁移率族成员家族3（TOX3）基因中的内含子变异体。对于其他四个参数（两侧之间的绝对差异；前乳头；后乳头和前乳头数量之间的比率；不存在或存在多余的乳头），仅在其他几条染色体上鉴定出了有意义的标记。这项研究进一步支持了VRTN的作用 该基因区域影响了意大利大白猪种群中奶头数量的记录变异性，并确定了一个基因组区域，该区域可能影响控制猪形态特征发育程序的生物学机制。