Bloom syndrome is a rare autosomal recessive genetic disorder due to mutation in BLM (RecQ protein-like 3). This disease is characterized by severe growth deficiency, an erythematous and photosensitive facial rash, dysmorphic features such as microcephaly and malar hypoplasia, immunodeficiency and a high predisposition to various types of cancer. The function of BLM as a helicase and its role during the regulation of homologous recombination (HR) is well characterized. Recently, the role of BLM as a DNA damage sensor has been revealed.