胱硫醚-β-合成酶基因多态性与精神分裂症的关联研究

目的 探讨胱硫醚-β-合成酶(CBS) 基因T833C、G919A多态性与精神分裂症的关系.方法 采用聚合酶链式反应(PCR)和DNA测序技术,对93例精神分裂症患者(病例组)和102例正常对照者(对照组)的CBS基因多态性进行检测.结果 ⑴所有受检者均未发现CBS基因T833C、G919A多态性,但在下游8-9内含子33bp处检测到G→A突变;病例组见G/A杂合和A/A纯合,对照组仅见G/A杂合.⑵病例组与对照组在G→A突变的基因型分布上差异无显著性(P>0.05),但病例组A等位基因频率(8.07%)高于对照组(3.43%)(χ2=3.92,P=0.048,OR=2.47,95%CI=1.01～6.05).⑶各临床亚组与对照组在G→A突变的基因型分布上差异无显著性(均P>0.05),但阳性组和晚发组A等位基因频率(8.70%,8.93%)高于对照组(3.43%) (χ2=4.35,P=0.037,OR=2.68,95%CI=1.06～6.77;χ2=4.29,P=0.038,OR=2.76,95%CI=1.06～6.43).结论 CBS基因T833C、G919A突变很低,可能与精神分裂症无关;CBS基因8-9内含子33bp处G→A突变可能是晚发、阳性型精神分裂症的风险因子之一.

Association study between cystathione-beta-synthase gene polymorphism and schizophrenia

Objective To explore the relationship between cystathione-beta-synthase(CBS) gene T833C,G919A polymorphisms and schizophrenia. Methods The CBS gene polymorphism was detected by polymerase chain reaction and DNA sequencing technique in 93 patients with schizophrenia and 102 healthy people as normal control. Results ⑴ No CBS gene T833C ,G919A polymorphisms were found in all subjects,but mutation of G→A was detected at the 33th base in intron 8-9. Both heterozygote G/A and homozygote A/A were found in patient group,only heterozygote G/A was found in control group. ⑵ There was no significant difference of genotype distribution for mutation of G→A between patient group and control group(P>0.05). The frequency of A allele in patient group (8.07%)was higher than that in control group(3.43%) (χ2=3.92,P=0.048,OR=2.47,95%CI=1.01～6.05). ⑶ There was no significant difference of genotype distribution for mutation of G→A between clinic subgroups and control group(all P>0.05). The frequency of A allele in positive subgroup(8.70%) and later first-onset age subgroup(8.93%) were higher than that in control group(χ2=4.35,P=0.037,OR=2.68,95%CI=1.06～6.77; χ2=4.29,P=0.038,OR=2.76,95%CI=1.06～6.43). Conclusion The finding suggests that mutation of CBS gene T833C ,G919A is very low and it may be not correlated with schizophrenia. Mutation of G→A at the 33th base in intron 8-9 of CBS gene may be one of risk factors for schizophrenia with later first-onset age or positive symptom.