聚集蛋白聚糖基因串联重复多态性与腰椎间盘突出症相关性研究

Association between the expression of Aggrecan and the distribution of Aggrecan gene variable number of tandem repeats with symptomatic lumbar disc herniation

目的 探讨人类聚集蛋白聚糖（Aggrecan）基因的表达及Aggrecan基因串联重复多态性（VNTR）与腰椎间盘突出症（LDH）的相关性.方法 收集2004年1月至2014年1月在中国医科大学附属第一医院骨科接受手术治疗且符合纳入和排除标准的89例患者及1 13名健康人的临床资料.病变组为患有LDH的患者74例,对照组为未患有LDH的脊柱创伤患者15例及健康人113名.收集每例手术患者切除的椎间盘和血液标本及健康人的血液标本.应用Western blot法检测两组患者椎间盘中Aggrecan蛋白的表达情况;应用RT-PCR技术检测两组患者血液中Aggrecan VNTR多态性分布情况.检测结果的比较采用Х^2检验.结果 Western blot检测结果显示,对照组椎间盘中Aggrecan蛋白的相对表达量高于病变组（对照组Aggrecan表达阳性率为86.67％,病例组Aggrecan表达阳性率为13.51％;Х^2=34.83,P＜0.05）.RT-PCR检测结果显示,病变组中等位基因25及等位基因21的基因频率高于对照组（A25病变组=22.97％,A25对照组=12.11％,Х^2A25=8.20,PA25=0.004;A21病变组=6.76％,A21对照组=0.39％,x2A21=14.35,PA21=0.000）.病变组不表达Aggrecan人群中有1个或2个≤等位基因25的个体,多于有2个＞等位基因25等位基因的个体（Х^2=5.69,P =0.017）;对照组二者分布无差异（Х^2 =0.29,P =0.590）.结论 LDH患者中Aggrecan等位基因25及21串联重复序列片段出现频率较高,Aggrecan与LDH有相关性;LDH患者中Aggrecan VNTR与Aggrecan的表达有相关性.

Objective To study the expression of Aggrecan and the relationship between the variable number of tandem repeats （VNTR） of Aggrecan and lumbar disc herniation （LDH）.Methods The disease group comprised of 74 patients already diagnosed with symptomatic LDH.The control group consisted of 15 patients restricted to spinal trauma and 113 healthy blood donors without symptoms of LDH who were not diagnosed with LDH.Disc tissue samples were obtained from surgical operations and blood samples were donated from all participants.The Aggrecan expression in isolated tissues was assessed by western blot using specific antibodies.The Aggrecan gene VNTR region was analyzed by PCR.Results The Aggrecan expression positive rate of control group was statistically and significantly higher （control group：86.67%,disease group：13.51% ; x2 =34.83,P 〈 0.05） than that of the disease group.Moreover,there was a statistically significant higher frequency of Allele 25 or Allele 21 in disease group compared to controls （A25disease group =22.97% A25control group =12.11% Х^2A25 =8.20,PA25 =0.004; A21disease group=6.76%,A21control group =0.39%,Х^2A21 =14.35,PA21 =0.000）.Compared to the participants with 2 Alleles 〉 25 repeats,subjects with 1 or 2 Alleles ≤25 repeats statistically and significantly over represented the disease group without the expression of Aggrecan （Х^2 =5.69,P =0.017）.Conclusions The findings suggest a relationship between Aggrecan and symptomatic LDH,where symptomatic LDH has a tendency of allele 21 and allele 25 repeats.In addition,an association between the distribution of Aggrecan gene VNTR polymorphism and the expression of Aggrecan is observed in symptomatic LDH.