- Mutation in BLM gene, which is a DNA helicase involved in DNA replication and homologous recombination DNA repair
- Severe growth retardation (intra-uterine and post-natal) and a sun-sensitive erythematous skin lesions, most commonly on the face. Recurrent infections, chronic pulmonary disease, and diabetes mellitus are common.
- Increased rate of mutation, leading high risk of cancer
- Inherited as autosomal recessive
- 300 cases reported
- Cancer risk:
- Cancer types resemble general population, but are much more frequent and occur much earlier
- Cancer most common cause of death