Sister chromatid exchanges in Bloom's syndrome
Archives of Dermatology
|May 1, 1978
Abstract:
The importance of chromosome instability in Bloom's syndrome is reviewed, and the recently developed technique for demonstrating sister chromatid exchanges (SCE) is described. In Bloom's syndrome, but not in other heritable syndromes associated with chromosome instability, there is a nine- to ten-fold increase in the frequency of spontaneous SCE. We present a case of Bloom's syndrome in which this test facilitated the diagnosis. In four obligate heterozygotes (the parents of children with Bloom's syndrome), however, an increase in the frequency of spontaneous SCE was not observed.
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