I’ve posted recently on Ashkenazi Jewish genetic diseases. Here’s one you don’t hear about that often: Bloom Syndrome. It’s is a condition that, although very rare in the general population, has much higher carrier rates among Ashkenazi Jews. What is Bloom Syndrome?
One in 100 Ashkenazi Jews are unaffected carriers – they carry one copy of the gene change that causes Bloom Syndrome. When two carriers have a child together, there is a 1 in 4 chance the child will have Bloom Syndrome. (See autosomal recessive inheritance )
People with Bloom Syndrome have characteristic appearances that include a long, narrow face, prominent nose and ears, and a smaller-than-average stature. The also have a tendency to develop patches of reddened skin on the face.
Affected individuals have a high susceptibility to infections and high risk of cancer, which arise unusually early in life and cause life expectancy to be shortened.
A diagnosis of Bloom Syndrome can be confirmed or ruled out by a laboratory test known as a chromosome study, which shows if blood and skin cells have a characteristic pattern of chromosome breakage and rearrangement.
The underlying causes of Bloom Syndrome cannot be treated, so medical intervention is primarily preventative.
Carrier screening to identify unaffected carriers before planning a pregnancy is available.