No abstract

ABSTRACT. Growth hormone (GH) plays an important role in promoting growth, protein and muscle accretion, and fat catabolism, suggesting that GH is a potential candidate gene affecting growth traits in vertebrates. In this paper, polymorphisms in GH were investigated in 632 Chinese Tibetan sheep, by using DNA sequencing. Three single nucleotide polymorphisms were identified, including two mutations (g.616G>A and g.624G>A) in intron 2 and one synonymous mutation (g.498G>C) in exon 2. Association analyses showed that both g.498G>C and g.616G>A were significantly associated with several growth traits (at P < 0.01 or P < 0.05) in three investigated breeds. Our results demonstrate that GH variation may be used as a molecular marker for growth traits in Chinese Tibetan sheep.

BackgroundThe aim of this study was to analyze potential influences of polymorphisms within the regulatory region of the bovine SIRT6 gene on carcass quality traits. Expression analyses suggested that SIRT6 gene is predominately expressed in kidney, compared with other tissues. In 535 indigenous Chinese beef cattle, two novel single nucleotide polymorphisms (SNPs) were identified within the promoter region of the SIRT6 gene.ResultsAssociation analysis indicated that G allele of the c.-1100 A > G had a positive effect on fat deposition, and the Hap4/4 diplotype had more favourable results than other dipoltypes with respect to the evaluation of carcass quality traits. Furthermore, promoter activity associated with the Hap3 haplotype was measured at higher levels than the Hap1 haplotype, which would be in agreement with the previously described association analysis.ConclusionThe SIRT6 promoter variants significantly affect transcriptional levels and subsequently significantly influence bovine intramscular fat content.