Instability of normal (CTG)n alleles in the DM kinase gene.
نویسندگان
چکیده
We report on a myotonic dystrophy (DM) family exhibiting instability of normal sized (CTG)n alleles in the DM kinase gene on the non-DM chromosome. At least two mutational events involving normal DM alleles must have occurred in this family; one was characterised as a 34-35 (CTG)n repeat mutation. These findings represent a dissociation between (CTG)n repeat instability and myotonic dystrophy. Furthermore, this family highlights genetic counselling issues relating to the pathogenicity of alleles at the upper end of the normal size range and the risk of further expansion into the disease range.
منابع مشابه
Presymptomatic diagnosis of myotonic dystrophy.
The discovery of an expanded (CTG)n repeat sequence in myotonic dystrophy (DM) has greatly improved our ability to detect DM gene carriers who have few or none of the classical signs of this disorder. We report here our experience with two such groups of gene carriers. We used a PCR based protocol that should be especially sensitive to small increases in CTG triplet number which might escape de...
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EDITOR—Myotonic dystrophy (DM) is the most common form of inherited neuromuscular disease in adults and is characterised by progressive muscle wasting and myotonia. The mutation responsible for DM has been identified as the amplification of a polymorphic (CTG)n repeat in the 3' untranslated region of a gene encoding a serine/threonine kinase (DMPK). The DM trinucleotide repeat is highly polymor...
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عنوان ژورنال:
- Journal of medical genetics
دوره 34 10 شماره
صفحات -
تاریخ انتشار 1997