河北省磁县食管癌贲门癌的遗传度及易感因素研究

目的:探讨磁县食管癌（含贲门癌）家庭聚集性及遗传因素在磁县食管癌病因中的作用，计算食管癌分离比及一级亲属遗传度。方法:采用病例-对照研究的方法，逐例入户调查了285 例食管癌的新发病例及1 415 例对照者的一级亲属食管癌患病及家族史等情况，比较其食管癌的患病率。用二项分布拟合优度χ2检验食管癌家庭聚集性；单病例法（Li-Mantel-Gart）计算分离比；Falconer 法计算遗传度。结果:食管癌先证者一级亲属发生率（12.80%），高于对照者一级亲属发生率（7.52%），差异有统计学意义（χ2=44.34，P=0.000）。 食管癌在家族中分布不符合二项分布，呈现明显的家族聚集性（χ2=288.19，P<0.0001）。 食管癌遗传度为（29.67± 4.32）% ，分离比0.181（95% CI:0.157～0.205），可认为属于多基因遗传病。结论:磁县食管癌是遗传因素和环境因素共同作用的结果，食管癌家族史增加食管癌发病风险。 

A Genetic Epidemiologiical Study on Esophageal and Cardia Cancers in Ci County of Hebei Prevince

Objective: To investigate roles of family aggregation and genetic factors of esophageal cancer (including cardia cancer) in Ci County, and compute the segregation ratio and heritability of first-degree relatives. Methods:A population based case-control study was conducted, including285 cases of esophageal cancer and 1,415 control cases. EC incidences in relatives of the patients and controls were compared byχ2 test and Heritability (h 2) was estimated using the Falconer method. Results: The results showed that the incident rate of the first-degree relatives in the patients was 12.80% , significantly higher than that in the control group (7.52% ) (χ2=44.34, P=0.000 ). EC in families did not fit the binomial distribution well, suggesting a familial aggregation ( χ2=288 .19, P<0.0001). The heritability of EC was 29.67± 4.32%. Segregation ratio was 0.1814 (95% CI was0.1574～0.2054) which is less than 0.25. It suggests that the genetic model occurring here is the polygenetic model. Conclusion:Findings suggest that the genetic factor is important in the occurrence of EC, as family aggregation exists among the EC patients in Ci County. A family history of upper gastrointestinal cancer increases the risk for EC.