Abstract: This study was conducted to analyze the polymorphisms of keratin-associated proteins (KAP) gene and aid to provide a theoretical foundation for molecular marker of wool production performance in tibetan sheep. The polymorphisms of partial sequence of KAP 3.2, KAP 7 and the exon of KAP 8 in plateau tibetan sheep were analyzed using PCR-SSCP. The results showed that there were polymorphisms in three gene locus, and were detected three genotypes (AA, AB, BB). The frequency of A allele was obviously higher than that of B allele, and the frequency of AA genotype was higher than AB and BB at KAP 3.2 locus, while the frequency of B allele was higher than A allele, and the frequency of BB genotype was higher than AA and AB at other two gene loci. The polymorphism was medium in KAP 3.2 and KAP 8 gene loci, while low in KAP 7 locus. The frequencies of genotype were deviated from the Hardy-Weinberg disequilibrium at KAP 3.2 and KAP 8 gene loci. The sequencing results showed that there was one mutation at 271 bp of KAP 3.2 and 1122 bp of KAP 8 gene, respectively, and there was one mutation at 102 bp of upstream regulatory region of KAP 7 gene. 

Key words: plateau tibetan sheep; keratin-associated proteins gene; single nucleotide polymorphism; PCR-SSCP