The association of very low-density lipoprotein receptor (VLDLR) haplotypes with egg production indicates VLDLR is a candidate gene for modulating egg production

Abstract

The very low-density lipoprotein receptor (VLDLR) transports egg yolk precursors into oocytes. However, our knowledge of the distribution patterns of VLDLR variants among breeds and their relationship to egg production is still incomplete. In this study, eight single nucleotide polymorphisms (SNPs) that account for 87% of all VLDLR variants were genotyped in Nick Chick (NC, n=91), Lohmann Brown (LohB, n=50) and Lueyang (LY, n=381) chickens, the latter being an Chinese indigenous breed. Egg production by NC and LY chickens was recorded from 17 to 50 weeks. Only four similar haplotypes were found in NC and LohB, of which two accounted for 100% of all NC haplotypes and 92.5% of LohB haplotypes. In contrast, there was considerable haplotypic diversity in LY. Comparison of egg production in LY showed that hens with NC-like haplotypes had a significantly higher production (p < 0.05) than those without the haplotypes. However, VLDLR expression was not significantly different between the haplotypes. These findings indicate a divergence in the distribution of VLDLR haplotypes between selected and non-selected breeds and suggest that the near fixation of VLDLR variants in NC and LohB is compatible with signature of selection. These data also support VLDLR as a candidate gene for modulating egg production.

A new molecular mechanism supports that blue-greenish egg color evolved independently across chicken breeds

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Research Note: Fine mapping of sequence variants associated with body weight of Lueyang black-boned chicken in the CCKAR gene

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The study of candidate genes in the improvement of egg production in ducks – a review

“…Recently, the potential role of expressions of insulin-like growth factor-1 ( IGF-1 ), prolactin receptor ( PRLR ), FSH , very low-density lipoprotein receptor ( VLDLR ), low-density lipoprotein receptor-related protein ( LRP ), estrogen receptor 1 ( ESR1 ), luteinizing hormone receptor ( LHR ), and estrogen receptor 2 ( ESR2 ) with egg traits have received serious attention ( Yao et al, 2010 ; Wang et al, 2016 ; Asiamah Amponsah et al, 2019 ; Cui et al, 2019 ; Asiamah et al, 2022 ).…”