Bloom's syndrome

Bloom syndrome (BLM, BLS, OMIM: 210900) is an autosomal recessive inherited chromosomal instability syndrome. The responsible gene (BLM, Bloom syndrome, RecQ helicase-like) is located in region 15q26.1. The normal gene product is one type of DNA helicase (RECQL3).

Already in the first year of life, those affected develop telangiectatic erythema that is sensitive to sunlight. Immunological manifestations include B-cell disorders with low levels of IgG, IgA, and IgM immunoglobulins with consequent susceptibility to infections. We also observe tendencies in cells to develop cytogenetic abnormalities, which often result in malignant transformation.