Genetic Association of The CYP7A1 Gene with Duck Lipid Traits

Cholesterol 7-hydroxylase (Cyp7a1) participates in lipid metabolism of liver, and its pathway involves catabolism of cholesterol to bile acids and excretion from the body. However, little is known about the effect of the polymorphisms of CYP7A1 gene on duck lipid traits. In the present study, seven novel synonymous mutations loci in exon 2 and exon 3 of CYP7A1 gene in Cherry Valley ducks were identified using PCR production direct sequencing. One novel SNP g.1033130 C>T was predicted in exon 2. Six novel SNPs g.1034076 C>T, g.1034334 G>A, g.1034373 G>A, g.1034448 T>C, g.1034541 C>G, and g.1034550 G>A were discovered in exon 3. Six haplotypes were detected using SHEsis online analysis software, and five loci (g.1034334G>A, g.1034373G>A, g.1034448T>C, g.1034541C>G, and g.1034550G>A) were in complete linkage disequilibrium, and as a block named Locus C3. By single SNP association analysis, we found that the g.1033130 C>T locus was significantly associated with IMF, AFP, TG, and TC (PT locus was significantly associated with AFP (P<0.05), and the locus C3 was significantly associated with TCH (P<0.05). Sixteen dipoltypes were detected by the combination of haplotypes, and demonstrated strong association with IMF, AFP, TG, and TCH (P<0.01). Therefore, our data suggested that the seven SNPs of CYP7A1 gene are potential markers for lipid homeostasis, and may be used for early breeding and selection of duck.