肺癌易感性与p73基因多态性关系的研究

目的探讨中国人群p73基因5’UTR区域两个单核苷酸多态性(G4C14，A4T14)与肺癌的关系。方法采用病例对照研究；选择经组织学确诊的肺癌病例425例，地区、年龄和性别频数匹配的对照588名，以聚合酶链反应-单链构象多态性方法进行多态性检测。结果此两个多态性之间具备完全的连锁不平衡，AT(A4T14)单倍型在病例组显著少于对照组(0．225 vs.0．287．P=0．0018)，提示变异的AT单倍型对肺癌具有保护作用。与携带p73 GC／GC单倍型基因型者比较，携带GC／AT单倍型基因型者肺癌风险降低30％(OR=0．70，95％CI：0．53～0．92)，而携带AT／AT单倍型基因型者肺癌风险降低55％(OR=0．70，95％CI：0．26～0．80)。结论p73基因多态改变可能与中国汉族人群肺癌遗传易感性有关。

Association of two genetic polymorphisms in the 5'' untranslated region of exon 2 of the p73 gene and risk of lung cancer

Objective To study the relationship between two potential functional polymorphisms in exon 2 of the p73 gene and the susceptibility of lung cancer. Methods Genotypes were determined by polymerase chain reaction-single stand conformation polymorphism(PCR-SSCP) method in 425 histologically-confirmed lung cancer cases and 588 cancer-free controls, frequency-matched by age and sex. Results The two polymorphisms were in complete linkage disequilibrium and the frequencies of variant p73 AT haplotype (A4T14) were less commonly seen in the cases ( 0.225 ) than in the controls ( 0.287 ) ( P = 0.0018 ). Compared with the p73 GC/GC homozygotes,both the AT/AT variant homozygotes and GC/AT heterozygotes were associated with a significantly decreased risk [adjusted odds ratio ( OR )= 0.45 ,95% confidence interval ( CI )= 0.26- 0.80 and OR = 0.70 ,95% CI = 0.53- 0.92 ,respectively]. Conclusion These results suggested that this p73 dinucleotide polymorphism might have had a role to play in the susceptibility of lung cancer.