Association of VLDLR haplotypes with abdominal fat trait in ducks

Abstract. This study aimed to determine the correlation among VLDLR (very low-density lipoprotein receptor) gene polymorphisms, body weight and abdominal fat deposition of Gaoyou ducks. A total of 267 Gaoyou ducks from one pure line was employed for testing. The polymorphisms of the VLDLR gene were screened by polymerase chain reaction and DNA sequencing. Four novel single nucleotide polymorphisms (SNPs) (g.151G  >  A, g.170C  >  T, g.206A  >  G and g.278–295del) were identified in the 5'-UTR and signal peptide region. Furthermore, eight haplotypes were identified based on the four SNPs. The H8 was the most common haplotype with a frequency of more than 31 %. The four SNPs and their haplotype combinations were shown to be significantly associated with body weight at 6–10 weeks of age (P < 0. 05 or P < 0. 01) and abdominal fat percentage (AFP) (P < 0. 05 or P < 0. 01). Remarkably, the H1H1 diplotype had an effect on increasing body weight and decreasing AFP from the 6th to the 10th weeks of age. However, increasing positive effects of the H5H8 diplotype were observed for both body weight and AFP. This study suggests that the VLDLR gene plays an important role in the regulation of body weight and fat-related traits and may serve as a potential marker for the marker-assisted selection program during duck breeding.