Familial risks for cervical tumors in full and half siblings: etiologic apportioning.
Many studies have shown familial aggregation for cervical cancer, but they have been unable to distinguish between shared environmental and genetic effects. Full and half-siblings were identified from the nationwide Swedish Family-Cancer Database, including invasive and in situ cervical cancers in women up to age 70 years. Half-siblings were defined through a common father or mother. Standardized incidence ratios, adjusted for several variables, were calculated for proband-wise risks between full and half-siblings. The familial risk for full siblings was 1.84, compared with 1.40 for maternal and 1.27 for paternal half-siblings. These data were used to apportion familial risk for cervical tumors in full siblings into a heritable component, accounting for 64%, and an environmental component, accounting for 36% of the total risk. No evidence for gene-environment interactions was found. The intractable difficulty in separating cervical cancer causation will be an obstacle for a successful identification of susceptibility genes.
Hemminki
Kari
K
Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Heidelberg. k.hemminki@dkfz.de
Chen
Bowang
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D002278:Carcinoma in Situ / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D004777:Environment; D005190:Family; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D012307:Risk Factors; D035781:Siblings; D013548:Sweden / Q000453:epidemiology; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics*