Identification and Association of SNPs in TBC1D1 Gene with Growth Traits in Two Rabbit Breeds

The TBC1D1 plays a key role in body energy homeostasis by regulating the insulin-stimulated glucose uptake in skeletal muscle. The present study aimed to identify the association between genetic polymorphisms of TBC1D1 and body weight (BW) in rabbits. Among the total of 12 SNPs detected in all 20 exons, only one SNP was non-synonymous (c.214G>A. p.G72R) located in exon 1. c.214G>A was subsequently genotyped among 491 individuals from two rabbit breeds by the high-resolution melting method. Allele A was the predominant allele with frequencies of 0.7780 and 0.6678 in European white rabbit (EWR, n = 205) and New Zealand White rabbit (NZW, n = 286), respectively. The moderate polymorphism information content (0.25<PIC<0.50) was present in both breeds. The association analysis revealed that genotypes GA and AA had higher 35 d body weight (BW) than genotype GG in both EWR (p<0.01) and NEW (p<0.05). For the 56 d BW and 70 d BW traits, genotypes AA and GA were higher than genotype GG in both two breeds, the difference was not significant (p>0.05). Our results implied that the c.214G>A of TBC1D1 gene might be one of the candidate loci affecting the trait of 35 d BW in the rabbit.