Variation in the Caprine Keratin-Associated Protein 27-1 Gene is Associated with Cashmere Fiber Diameter

• Main Authors: Mengli Zhao, Huitong Zhou, Yuzhu Luo, Jiqing Wang, Jiang Hu, Xiu Liu, Shaobin Li, Zhiyun Hao, Xiayang Jin, Yize Song, Xinmiao Wu, Liyan Hu, Jon G. H. Hickford
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Genes
• Subjects: KAP27-1 gene (<i>KRTAP27-1</i>); mean fiber diameter; skin; Longdong cashmere goats
• Online Access: https://www.mdpi.com/2073-4425/11/8/934

Variation in some caprine keratin-associated protein (KAP) genes has been associated with cashmere fiber traits, but many KAP genes remain unidentified in goats. In this study, we confirm the identification of a KAP27-1 gene (<i>KRTAP27-1</i>) and describe its effect on cashmere traits in 248 Longdong cashmere goats. A polymerase chain reaction–single strand conformation polymorphism (PCR-SSCP) analysis was used to screen for sequence variation in this gene, and three sequence variants (named <i>A</i> to <i>C</i>) were found. These sequences have the highest similarity (77% identity) to a human <i>KRTAP27-1</i> sequence, while sharing some homology with a predicted caprine <i>KRTAP27-1</i> sequence ENSCHIG00000023347 in the goat genome construct (ARS1:CM004562.1) at chromosome 1 position 3,966,193–3,973,677 in the forward strand. There were two single nucleotide polymorphisms (SNPs) detected in the coding sequence, including one nonsynonymous SNP (c.413C/T; p.Ala138Val) and one synonymous SNP (c.495C/T). The <i>C</i> variant differed from <i>A</i> and <i>B</i> at c.413C/T, having cytosine in its nucleotide sequence, while the <i>B</i> variant differed from <i>A</i> and <i>C</i> at c.495C/T, having thymine in its nucleotide sequence. Goats of the genotypes <i>AB</i> and <i>BB</i> produced cashmere fibers of higher mean fiber diameter (MFD) than goats of genotype <i>AA</i>, but no difference in MFD was detected between the <i>AB</i> and <i>BB</i> goats. These results suggest that <i>B</i> is associated with increased MFD. Expression of the caprine <i>KRTAP27-1</i> sequence was predominantly detected in the skin tissue of goats but not or only weakly detected in other tissues, including longissimus dorsi muscle, heart, kidney, liver, lung and spleen.