The Association Between Novel Polymorphisms of Gremlin Genes and Egg-Laying Performance Traits in Chinese Village Dagu Hens

Gremlin (GREM1, GREM2) genes are the known bone morphogenetic proteins (BMPs) inhibitors, but their genetic diversity in animal species remains unknown. The current study was conducted to investigate single nucleotide polymorphisms (SNPs) in chicken GREM1 and GREM2 genes, and their association with egg production traits using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and deoxyribonucleic acid (DNA) sequencing. The results discovered novel SNPs and, among these variations, C/T transition at position 436 in exon 1 of the GREM1 gene leads to synonymous substitution of amino acids, and T/C transition at position 690 in the coding region of the GREM2 gene leads to a non-synonymous substitution of amino acids (valine acid 114-to-alanine acid). Association analysis established that at the age of 43, 57 and 66 wks, hen-house egg production (HHEP) was more highly significantly associated (P<0.05) with the AA genotype in the GREM1 gene. In the GREM2 gene, the TC genotype was remarkably linked with higher HHEP at the age of 30, 57 and 66 wks. Our results provide evidence that the GREM1 and GREM2 genes have potential effects on HHEP in chickens. SNPs determined in this work may be utilised as favourable potential DNA markers for improving of egg-laying performance traits.