Epiloia in twins: a problem in diagnosis and counselling.

A family is reported in which the sixth and seventh children, who are twins, have epiloia. No other member of the family has any of the accepted stigma of this condition. It is shown that the twins are dizygotic and so are likely to have inherited their epiloia. Biochemical studies suggest that the father has epiloia and, in view of this, pigmented skin lesions assume diagnosis importance. The significance of this is discussed both in relation to diagnosis in general and to genetic counselling in this family where one of the other children might be affected.