精神分裂症患者单胺氧化酶A和B基因的连锁不平衡研究

目的　探讨精神分裂症患者单胺氧化酶A(MAOA)和B(MAOB)基因间连锁不平衡。方法　采用聚合酶链反应和微卫星DNA重复序列多态性技术 ,对上海地区 82例精神分裂症患者和88名健康者作了MAOA(CA)n和MAOB(GT)n两种微卫星DNA的多态性分析。结果　 (1 )MAOA(CA)n基因座的等位基因与精神分裂症无关联 (P >0 0 5) ;(2 )MAOB(GT)n基因座中 1 76bp等位基因与精神分裂症呈正关联 ,相对危险度 (RR) =8 2 0 (χ2 =7 42 ,P <0 0 5) ;(3) 1 1 6/ 1 76单体型与精神分裂症也呈正关联 ,RR =5 39(χ2 =4 2 6 ,P <0 0 5) ;(4) 1 1 6/ 1 76单体型的连锁不平衡系数 (δ)在患者组和对照组中分别为 0 0 30 9(t=3 0 9,P <0 0 5)和 0 0 0 5 1 (t=1 0 1 ,P >0 0 5) ,患者组中δ的差异有显著性。结论　MAOB基因与精神分裂症正关联 ,而MAOA和MAOB基因间的连锁不平衡可能与精神分裂症的发病风险相关

Linkage disequilibrium between polymorphic loci for monoamine oxidases A and B and schizophrenia

Objective To investigate linkage disequilibrium between polymorphic loci for monoamine oxidases A and B and schizophrenia in Chinese Methods Eight two schizophrenics and 88 controls in Shanghai area were involved Two X linked microsatellites, (AC)n repeats in the MAOA gene and (GT)n repeats in the MAOB gene were determined with amplified fragment length polymorphism (Amp FLP) techniques Results (1) There were no association between the MAOA (CA)n loci and schizophrenia (2) The 176 bp allele for MAOB gene was associated with schizophrenia ( RR =8 20, P <0 05) (3) The 116/176 haplotype with a relative risk of 5 39 ( P <0 05) was also observed in schizophrenia (4) The coefficient of linkage disequilibrium for 116/176 haplotype was 0 005 1 ( t =1 01, P >0 05) in control subjects and 0 030 9 ( t =3 09, P <0 05) in schizophrenics Conclusions It is suggested the linkage disequilibrium of MAOA and MAOB might contribute to the risk for schizophrenia in our samples