Polymorphisms in theASMTandADAMTS1gene may increase litter size in goats

Prolificacy of most local goat breeds in China is low. Jining Grey goat is one of the most prolific goat breeds in China, it is an important goat breed for the rural economy. ASMT (acetylserotonin O-methyltransferase) and ADAMTS1 (ADAM metallopeptidase with thrombospondin type 1 motif) are essential for animal reproduction. Single nucleotide polymorphisms (SNPs) ofASMTandADAMTS1genes in the highly prolific breed (Jining Grey goats), medium prolific breed (Boer goats and Guizhou White goats) and low prolific breeds (Angora goats, Liaoning Cashmere goats and Inner Mongolia Cashmere goats) were detected by polymerase chain reaction-restriction fragment length polymorphism and sequencing. Two SNPs (g.158122T>C, g.158700G>A) ofASMTgene and two SNPs (g.7979798A>G, g.7979477C>T) ofADAMTS1gene were identified. For g.158122T>C ofASMTgene, further analysis revealed that genotype TC or CC had 0.66 (p < 0.05) or 0.75 (p < 0.05) kids more than those with genotype TT in Jining Grey goats. No significant difference (p > 0.05) was found in litter size between TC and CC genotypes. The SNP (g.158122T>C) caused a p.Tyr298His change and this SNP mutation resulted in changes in protein binding sites and macromolecule-binding sites. The improvement in reproductive performance may be due to changes in the structure of ASMT protein. For g.7979477C>T ofADAMTS1gene, Jining Grey does with genotype CT or TT had 0.82 (p < 0.05) or 0.86 (p < 0.05) more kids than those with genotype CC. No significant difference (p > 0.05) was found in litter size between CT or TT genotypes. These results preliminarily indicated that C allele (g.158122T>C) ofASMTgene and T allele (g.7979477C>T) ofADAMTS1gene are potential molecular markers which could improve litter size of Jining Grey goats and be used in goat breeding.