CLEVELAND—Both genetic and environmental factors affect skin photoaging, according to a study of twins conducted by researchers from Case Western and the Cleveland Clinic Foundation (Arch Dermatol. 2009;145(12):1375-1379). During the annual Twins Days Festival in Twinsburg, Ohio, 65 volunteer sets of monozygotic (MZ) and dizygotic (DZ) twins completed a survey about history of skin cancer, smoking and drinking habits; clinicians assigned a clinical photodamage score to each participant.
Photodamage scores among twins of a pair, regardless of type, were highly correlated (P=0.92). History of skin cancer, lower weight and cigarette smoking predicted higher levels of photodamage, as did zygosity status, which was more pronounced for MZ versus DZ. Alcohol consumption was significantly associated with lower photodamage scores (P=0.003).