原发性开角型青光眼患者Myocilin基因的单核苷酸多态性

目的　探讨 Myocilin(MYOC)基因的单核苷酸多态性 (single nucleotide polymorphisms,SNPs)及其与原发性开角型青光眼 (primary open- angle glaucoma,POAG)发病的关系。方法　应用高通量构象敏感性凝胶电泳和荧光标记自动测序法筛选和鉴定香港 15 7例 POAG散发患者和 15 5名对照 MYOC基因的 SNPs。结果　在 MYOC基因所有 3个外显子及邻近的非编码区共检出 17种 SNPs:1- 83G→ A、G12 R、P16 L、A17S、R4 6 X、R76 K、R91X、T12 3T、D2 0 8E、L 2 15 P、730 35 A→ G、A2 6 0 A、I2 88I、E30 0 K、T35 3I、Y4 71C和 15 15 73G→ C。其中 ,R91X、E30 0 K和 Y4 71C仅在 POAG患者中检测到。此外 ,15 15 73G→ C各基因型在 POAG患者与对照人群中的分布差异具有显著意义 ,POAG患者中 CG型频率为 0 .6 % ,低于对照组的 4 .5 % (P=0 .0 36 )。其余 16种 SNPs各基因型在两组人群中的分布差异均无显著意义。结论　 MYOC基因多态性可能与中国人 POAG发病有关 ,提示 MYOC基因是 POAG的相关基因。

Single nucleotide polymorphisms of the myocilin gene in primary open-angle glaucoma patients

OBJECTIVE: To detect single nucleotide polymorphisms (SNPs) of the myocilin (MYOC) gene and to investigate their associations with primary open-angle glaucoma (POAG). METHODS: One hundred and fifty-seven sporadic patients with POAG and 155 unrelated control subjects without POAG were recruited from staff and visitors to the Prince of Wales Hospital between 1998 and 2000. All study subjects are ethnic Chinese living in Hong Kong. The two populations were matched in frequencies of gender and age. The SNPs of the MYOC gene in POAG patients and control subjects were screened and identified by high throughout conformation sensitive gel electrophoresis and fluorescent labeling automated sequencing. The genotype frequencies of each SNP in the two groups were compared by the Chi2 test or Fisher's exact 2-tailed test. RESULTS: A total of seventeen SNPs were identified from 2172 bp long of the MYOC gene, including all 3 exons and adjacent non-coding regions. The identified SNPs were 1-83G --> A, G12R, P16L, A17S, R46X, R76K, R91X, T123T, D208E, L215P, 730+35A --> G, A260A, I288I, E300K, T353I, Y471C and 1515+73G --> C, respectively. Of these, R91X, E300K and Y471C were found only in POAG patients. A significant difference between POAG patients and control subjects was found in the genotype frequencies of 1515+73G --> C. The frequency of the heterozygote (CG) was 0.6% in POAG patients, significantly less than the 4.5% in control subjects (Fisher's exact 2-tailed test, P=0.036, OR=0.136, 95%CI=0.022-0.828). No significant difference was found between the two populations in genotype frequencies of all other SNPs. CONCLUSION: The polymorphisms of the MYOC gene may be related to POAG.