Stearoyl-CoA desaturase (SCD) gene polymorphism in goat breeds

Abstract

There is evidence that stearoyl-CoA desaturase (SCD) is a key enzyme for lipid metabolism. Changes in enzyme activity that depends on SCD gene polymorphism and regulation could cause variations of fatty acid composition of meat and milk. We investigated genetic variability in caprine SCD, analyzing 335 animals belonging to three goat breeds by single-strand conformation polymorphism and DNA sequencing. Six single nucleotide polymorphism were identified, in intron 3 (585T-->A and 601A-->G; Ref. AF422168), intron 4 (719T-->A; AF422169), and exon 6 (690 A-->G, 718 C-->G, and 802 A-->C; AF422171). The less polymorphic SNP 601A-->G displayed variability only in Xuhuai and Boer breeds. Across breeds, the average frequency for the least frequent alleles ranged from 0.1158 to 0.2532. The three SNPs in exon 6 resulted in variations of amino acids 313 tyr --> cys, 322 phe --> leu, and 350 arg --> ser. The allelic distribution in exon 6 of Xuhuai was significantly different from Boer and Haimen.