Genetic variants in SCNN1B and AHCYL1 are associated with eggshell quality in Chinese domestic laying ducks (Anas platyrhynchos).

1. The objective of this study was to investigate the evolution of SCNN1B and AHCYL1 proteins among 10 domestic avian and mammalian animal species, to uncover the expression patterns of SCNN1B and AHCYL1 genes in ducks, identify the genetic variants of the SCNN1B and AHCYL1 genes and analyse their effects on eggshell quality.2. Expression profiles of the SCNN1B and AHCYL1 genes in Sansui female ducks were determined using real-time fluorescence quantitative PCR to identify SNPs. The duck SCNN1B and AHCYL1 genes were amplified to identify SNPs. A total of 502 Sansui female ducks were genotyped by sequencing, and the associations between the mRNA expression/SNP genotypes and 6 eggshell quality indices were analysed using PASW Statistics 18.0.3. The results showed that the SCNN1B and AHCYL1 proteins are highly conserved in different mammalian or domestic animals, especially the AHCYL1 protein. The SCNN1B and AHCYL1 genes were widely expressed in different tissues of male and female ducks, and expression level in the uterus was greater than in other tissues. The expression of SCNN1B and AHCYL1 during the oviposition cycle indicated that expression levels were related to the eggshell mineralisation stage.4. The mRNA expression levels of the uterine SCNN1B and AHCYL1 genes were positively correlated with eggshell strength (ESS), percentage (ESP) and weight (ESW) (P < 0.05), respectively. Ten novel SNPs in SCNN1B and AHCYL1 genes from Chinese domestic laying ducks were identified through PCR amplicon sequencing.5. Genetic association analysis indicated g.797509 C > T, g.797573 C > T and g.797834 C > T in SCNN1B gene and g.169244 T > A, g.169265 T > C and g.175311 T > C in AHCYL1 gene had a significant effect on eggshell quality. Correlation analysis between the SNP genotype and SCNN1B and AHCYL1 genes expression in the uterus showed that the genotypes of g.797509 C > T, g.797573 C > T, g.797834 C > T, g.169244 T > A and g.175311 T > C sites affected the expression of SCNN1B and AHCYL1 genes in utero (P < 0.05).6. The study indicated SCNN1B and AHCYL1 as candidate genes to improve eggshell traits in ducks.

Association of three SNPs in adiponectin gene with lipid traits of Tianzhu Black Muscovy (Cairina moschata).

Adiponectin plays a critically biological role in atherosclerosis, glucose utilization, lipid and carbohydrate metabolism, and triglyceride synthesis in animals and humans. However, little is known about the effect of adiponectin on lipid metabolism of the avian species. The aim of the preset study was to investigate the potential associations between adiponectin gene single nucleotide polymorphisms (SNPs) and the lipid traits in 348 females of Tianzhu Black Muscovy. Three novel SNPs (167G>A, 290T>C and 711G>A) were detected in adiponectin gene. 167G>A and 290T>C has linked very closely, and then 711G>A with 167G>A and 290T>C has no strong linkage disequilibrium, respectively. The Chi square test showed that allelic frequency and genotype frequency of two SNPs (167G>A and 711G>A) didn't agree with the Hardy-Weinberg equilibrium (P>0.05). Four haplotypes and nine diplotypes were formed on the three SNPs of adiponectin gene. Association analysis indicated that the 167G>A genotypes were strongly associated with intramuscular fat (IMF) of chest muscle and serum total cholesterol (TC) (P < 0.01); the 290T>C genotypes were strongly associated with IMF, TC, and serum triglyceride (TG) (P < 0.01); furthermore, the 711G>A genotypes were significantly associated with TG and TC (P < 0.05); the diplotypes were strongly associated with IMF, TC, and TG (P < 0.01). Therefore, three SNPs in adiponectin were potential markers for improving IMF in Muscovy ducks.