Genetic Epidemiology

这个遗传流行病学项目中的许多调查来自于对癌症高危家庭的观察或其他病因学研究。继续对大都市区犹太人口调查的数据进行分析。评估了乳腺癌后第二种癌症的风险。突变携带者患对侧乳腺癌的风险并不显著高于非携带者。然而，第二次卵巢癌的风险更高。对56例髓母细胞瘤患者和159例急诊室对照患者的头颅CT研究进行回顾性审查，发现9%的无分流管髓母细胞瘤患者、16%的有分流管的髓母细胞瘤患者和10%的急诊室对照患者有大脑镰钙化。 然而，只有两名同时患有髓母细胞瘤和痣样基底细胞癌综合征的患者在围诊断期表现出大脑镰钙化。在Beckwith-Wiedemann综合征患者中，约25%的患者有非恶性肾脏异常，包括髓质肾囊肿、肾盏憩室、肾积水和肾结石。作为刚刚完成的DCEG成人脑肿瘤综合病例对照研究的后续研究，正在对480例符合条件的胶质瘤病例的父母、兄弟姐妹和成年子女进行以家庭为基础的研究。亲属将接受采访，了解个人和家庭病史以及其他风险因素，并将被要求提供口腔细胞作为DNA来源。在关联研究和分析中，亲属将被用作神经胶质瘤病例的对照，以评估遗传易感性和环境暴露对神经胶质瘤和病因相关肿瘤风险的作用。流行病学和遗传学方法研究基因-环境相互作用进行了审查。传统的流行病学方法有足够的力量来检测共同的遗传和/或环境因素的研究中的相互作用。然而，罕见因素的研究可能需要替代研究设计，如多阶段抽样，配对或病例病例设计。

Many of the investigations in this genetic epidemiology project arise from observations in families at high risk of cancer or in other etiologic studies. Analyses of the data from the survey of the Jewish population in the metropolitan D.C. area continued. Risks of second cancers following breast cancer were assessed. The risk of contralateral breast cancer was not significantly higher among mutation carriers compared to noncarriers. Risk of a second ovary cancer, however, was higher. Retrospective review of cranial CT studies in 56 patients with medulloblastoma and 159 emergency room controls revealed that 9% of medulloblastoma patients without shunts, 16% with shunts, and 10% of emergency room controls had falx calcification. Only the two patients with both medulloblastoma and the nevoid basal cell carcinoma syndrome, however, demonstrated falx calcification in the peridiagnostic period. Among individuals with Beckwith-Wiedemann syndrome, approximately 25% have nonmalignant renal abnormalities including medullary renal cysts, caliceal diverticula, hydronephrosis and nephrolithiasis. As a follow-up to a just completed DCEG comprehensive case-control study of adults with brain tumors, a family-based study of the parents, siblings and adult children of the 480 eligible glioma cases is being conducted. Relatives will be interviewed about personal and family medical history and other risk factors and will be asked to provide buccal cells as a source of DNA. The relatives will be used as controls for the glioma cases in association studies and in analyses to evaluate the roles of genetic susceptibility and environmental exposures on the risk of gliomas and etiologically related tumors. Epidemiologic and genetic approaches for examining gene-environment interaction were reviewed. Traditional epidemiologic approaches have sufficient power to detect interaction in studies of common genetic and/or environmental factors. Studies of rare factors, however, will likely require alternative study designs such as multi-stage sampling, countermatching or case-case designs.