Department of Health and Welfare of Animals, University of Studies of Bari Italy, Strada Prov. le per Casamassima Km 3, 70010 Valenzano (Ba), Italy.
Mol Biol Rep. 2011 Nov;38(8):5387-92. doi: 10.1007/s11033-011-0691-8. Epub 2011 Mar 9.
In mammals, the STAT proteins (signal transducers and activators of transcription) are a group of cytoplasmic transcription factors that mediate the actions of many peptide hormones and cytokines within target cells. In this study, the STAT5A/AvaI polymorphism was investigated with the PCR-RFLP technique in a sample of 191 Jersey cows reared in southern Italy. This polymorphism is localized in the coding region of the bovine STAT5A gene. It is a substitution C → T at position 6853 within the exon 7. All the possible genotypes for the C/T polymorphism were identified. The overall frequencies of alleles C and T were 0.75 and 0.25 respectively. In order to study the relationship between this SNP and milk production traits, data for 305-day milk production were used. Significant differences between CC and CT genotypes were found in milk yield (MY), fat yield (FY), solids not fat (SNF) yield, total solids (TS) yield (P < 0.01) and protein yield (PY) (P < 0.05). In particular the CC cows produced more milk than CT ones (6196.07 vs. 5744.66 kg) without differences in protein and fat content. As a consequence, CC cows yielded more fat, protein, solids not fat and total solids than CT. As far as concerns lactose and ash contents and the fat/protein ratio, no significant difference was found between the two genotypes. Even if further studies should be carry out to assess the role of this SNP on production traits, it is possible to conclude that STAT5A/AvaI polymorphism seems to be a promising indirect marker to improve milk production traits in cattle.
在哺乳动物中，STAT 蛋白（信号转导和转录激活因子）是一组细胞质转录因子，可介导许多肽激素和细胞因子在靶细胞中的作用。本研究采用 PCR-RFLP 技术，对意大利南部饲养的 191 头泽西奶牛的 STAT5A/AvaI 多态性进行了研究。该多态性位于牛 STAT5A 基因的编码区。它是第 7 外显子 6853 位的 C→T 取代。确定了 C/T 多态性的所有可能基因型。等位基因 C 和 T 的总体频率分别为 0.75 和 0.25。为了研究该 SNP 与产奶量性状的关系，使用了 305 天产奶量数据。在产奶量（MY）、脂肪产量（FY）、非脂固形物产量（SNF）、总固形物产量（TS）和蛋白质产量（PY）方面，CC 和 CT 基因型之间存在显著差异（P<0.01）。特别是 CC 奶牛的产奶量高于 CT 奶牛（6196.07 比 5744.66kg），而蛋白质和脂肪含量没有差异。因此，CC 奶牛的脂肪、蛋白质、非脂固形物和总固形物产量高于 CT 奶牛。就乳糖和灰分含量以及脂肪/蛋白质比而言，两种基因型之间没有发现显著差异。尽管应进一步开展研究以评估该 SNP 对产奶量性状的作用，但可以得出结论，STAT5A/AvaI 多态性似乎是一种有前途的间接标记，可提高奶牛产奶量性状。
