Search resultsDeterminants of melanoma in a case-control study of twins (United States)
Title
Determinants of melanoma in a case-control study of twins (United States)
Publication type
Journal Article
Year of Publication
2001
Authors
Journal
Cancer Causes and Control
Volume
12
Issue
7
Pagination
615 - 625
Date published
2001
ISBN
09575243 (ISSN)
Keywords
Adolescent, Adult, Aged, article, cancer risk, cancer susceptibility, Case-Control Studies, Confidence Intervals, controlled study, Diseases in Twins, Eye Color, Female, human, Humans, major clinical study, male, melanoma, Middle Aged, nevus, Odds Ratio, prevalence, priority journal, Registries, risk factor, Risk Factors, Skin Neoplasms, Skin Pigmentation, sun exposure, sunburn, sunlight, Twin studies, twins, Twins, Dizygotic, Twins, Monozygotic, United States
Abstract
Objectives: To estimate the relative contribution of environmental and genetic factors disposing towards the development of melanoma. Methods: We investigated risk factors for melanoma in a case-control study conducted among 185 North American twin pairs in which one was diagnosed with melanoma and the other (the co-twin of the case) was not. We considered monozygous (MZ) and dyzygous (DZ) twins separately. Results: While greater risk of melanoma was associated with number of large nevi in DZ twins (adjusted OR = 26.6 (4.2-170.8) for three or more large moles), this was not the case for MZ twins (adjusted OR = 1.4 (0.6-3.2) for three or more large moles). Elevated risks of developing melanoma with site-specific sun exposures resulting in sunburn also appeared to be confined to DZ twins. Despite the number of identical twins reporting a difference in mole prevalence, we observed only a modest and inconsistent increase in melanoma risk attributable to that factor, whereas the increase within fraternal twin pairs was larger by an order of magnitude. Conclusions: If confirmed, this indicates that the significance of mole prevalence as a risk factor for melanoma is largely as a genetic, rather than an environmental, factor. We noticed an increased risk of developing melanoma among DZ twins who drank moderate amounts of beer, but we believe this result may be due to the sun-exposure activities of those people most likely to drink moderate amounts of beer.