Bloom Syndrome (BLM)
Bloom syndrome is an autosomal recessive disorder caused by pathogenic variants in the BLM gene, which has a higher frequency among individuals of Ashkenazi Jewish descent. The disorder causes short stature and sun-sensitive skin, subsequently placing affected individuals at an increased risk of cancer with onset in the third to fourth decade of life. Gastroesophageal reflux and learning disability are also possible symptoms observed in Bloom syndrome. Women usually have reduced fertility and experience early menopause; typically, men are infertile. Due to increased cancer susceptibility, prognosis and life expectancy is generally unfavorable. The severity of the disease cannot be predicted based on the inherited variants.
For information about carrier frequency and residual risk, please see the residual risk table.