Bloom syndrome

Patients have small bodies, usually exhibit an erythematous (red skin produced by capillary congestion) "butterfly rash" that is sensitive to sunlight, excessive hyper- and hypopigmented skin lesions located anywhere on the body, and a high rate of bacterial infections due to immunodeficiency. These children are prone to cancer, chronic lung disease, and diabetes. Bloom syndrome is more common among Ashkenazi Jews than any other population.