Evaluation of the skin cancer risk among heterozygotes bearing a founder mutation allele unique to a Japanese population at xeroderma pigmentosum group A (XPA) gene

本研究的目的是通过比较非黑色素瘤皮肤癌患者与对照人群中XPA基因中携带创始者突变的杂合子的频率来评估杂合子的癌症风险，通过利用XPA基因的创始者突变在日本人群中以相对高的频率存在并且可以使用PCR容易地发现的事实，我们在对照人群的682个个体中发现了5个杂合子，在915个非黑色素瘤皮肤癌中发现了13个杂合子。两组的频率之间没有显著性差异。虽然从我们以前的研究中获得的频率意味着在日本人群中有大约100万个XPA创始人突变的杂合子，但本研究显示，XPA创始人突变的杂合子频率在非黑色素瘤皮肤癌中并不高于对照人群。

The aim of this study is to evaluate the cancer risk of heterozygotes by comparing the frequency of heterozygotes bearing a founder mutation in the XPA gene in nonmelanoma skin cancer patients to control population, by taking advantage of the fact that a founder mutation at the XPA gene exists at a relatively high frequency among the Japanese population and can be found easily using the PCR-RFLP method.We found 5 heterozygotes among 682 individuals in a control population and 13 heterozygotes among 915 nonmelanoma skin cancers. There was no statistically-significant difference between the frequencies of both groups. Although the frequency obtained from our previous study implies that there are about 1 million heterozygotes of the XPA founder mutation in the Japanese population, this study revealed that the frequency of heterozygotes of XPA founder mutation was not higher among nonmelanoma skin cancers than that in the control population.