Investigation of TG gene variants and their effects on growth, carcass composition, and meat quality traits in Chinese steers.

Thyroid hormones play an important role in regulating metabolism and can affect metabolism-related traits such as fat deposition. The thyroglobulin (TG) gene produces the precursor of thyroid hormones and has been proposed as a candidate gene for a quantitative trait locus with an effect on fat deposition. In this study, we identified 4 novel single nucleotide polymorphisms (SNPs) in the 5' flanking region of the TG gene using a DNA sequencing method. The SNP marker association analysis indicated that the T1355C SNPs were significantly associated with meat percentage (P < 0.05). A significant association between the G1356A polymorphism and live weight and loin muscle area was also detected (P < 0.05). However, no significant association was found between 4 SNPs and the other growth, carcass composition, and meat quality traits including intramuscular fat. The results of this study suggest