Genetic and environmental factors in scleroderma.

Recent epidemiologic research on scleroderma has been directed toward both genetic and environmental factors. The nature of any genetic contribution is unknown, although the major histocompatibility complex region is important in determining antibody response. Environmentally, an occupational basis in a small proportion of cases seems likely. There is no evidence to support the hypothesis that silicone gel breast implants are an important risk factor in the development of scleroderma.