中文摘要：

目的 COL9A1基因是位于单纯性马蹄内翻足（ICTEV）易感区域（6q12-13）的已知基因。本研究探讨COL9A1基因在ICTEV患者中的表达及其单核苷酸多态（SNP）位点在ICTEV和正常人中的分布情况。方法应用免疫组化方法检测25例ICTEV患儿及5例正常对照组肌肉及肌腱组织中COL9A1的表达;应用限制性片段长度多态性技术结合测序法,分析118例ICTEV患者及100名正常人COL9A1基因的2个SNP位点基因型。结果 88%（22/25）的ICTEV患者COL9A1蛋白表达阳性,明显高于正常对照组。位于COL9A1基因编码区的SNP位点rs1135056的基因型频率和等位基因频率在两组人群中的分布差异有统计学意义（P〈0.05）：ICTEV组G等位基因频率高于对照组;与对照组相比,AA基因型频率降低,AG、GG基因型频率增高。结论 COL9A1基因在ICTEV中高表达,rs1135056多态位点G等位基因和ICTEV的发生相关。

英文摘要：

Objective COL9A1 gene is located in the susceptibility region of idiopathic congenital talipes equinovarus（ICTEV）（6q12-13）.This study aimed to investigate the expression of the COL9A1 gene and the distribution of single nucleotide polymorphism（SNP） of COL9A1 gene in patients with ICTEV and normal controls.Methods Immunohistochemistry was used to detect the expression of COL9A1 in 25 children with ICTEV and 5 normal controls.The frequencies of genotypes and allele of two SNPs in COL9A1 gene rs35470562 and rs1135056 were investigated by PCR-restriction fragment length polymorphism（PCR-RFLP） and DNA sequencing in 118 patients with ICTEV and 100 normal controls.Results The COL9A1 protein expression was significantly higher in 22（88%） out of 25 children with ICTEV than normal controls.There were significant differences in the frequencies of genotypes and allele of rs1135056 in COL9A1 gene between the ICTEV and the control groups： the G allele frequency was higher,the frequency of AA genotype was lower,and the frequencies of AG and GG genotypes were higher in ICTEV patients than those in healthy controls（P〈0.05）.Conclusions COL9A1 protein is highly expressed in patients with ICTEV and rs1135056,which is located in the coding region of COL9A1 gene,may be associated with the pathogenesis of ICTEV.