Genetic Epidemiological Analysis of Esophageal Cancer in High-incidence Areas of China

Genetic epidemiological studies have shown that genetic susceptibility to esophageal cancer (EC) is animportant cause of its high incidence within families in some areas of China. The purpose of this study was toobtain evidence of a genetic basis of EC in Xin-an and Xin-xiang counties in China. Familial aggregation andcomplex segregation analyses were performed of 79 EC families in these counties. The heritability of EC wasexamined using Falconer’s method and complex segregation analysis was conducted with the SEGREG programin Statistical Analysis for Genetic Epidemiology (SAGE version 5.3.1). The results showed that the distribution ofEC in families did not fit well into a binomial distribution. The heritability of EC among first-degree and seconddegreerelatives was 67.0±7.31% and 43.1%±9.80%, respectively, and the summing up powered heritability was53.2±6.74%. The segregation ratio was 0.045. Complex segregation analysis showed that the genetic model ofEC was additive. The current results provide evidence for an inherited propensity to EC in certain high-riskgroups in China, and support efforts to identify the genes that confer susceptibility to this disease.