Large deletion in the NF1 gene associated with dysmorphism
- University Hospital of Wales, Cardiff (United Kingdom); and others
Neurofibromatosis type 1 is an autosomal dominant disorder with a prevalence of 1 in 3000. The major clinical features of the disease include cafe-au-lait spots, neurofibromas, Lisch nodules and auxillary freckling. Six sporadic NF1 patients with dysmorphism and intellectual impairment have been described to have a large deletion extending beyond the NF1 gene. We report another spordiac NF1 patient with severe developmental delay, early growth failure and dysmorphism (not Noonan-like) associated with a large deletion involving the NF1 gene. A panel of 12 polymorphic DNA markers within 4 cM of the NF1 gene were used to screen for the NF1 gene rearrangements. With all the polymorphic markers, only a single band was ever observed in this affected individual. However, with DNA probe EW301 which maps to 17p, a biparental inheritance was observed. Analysis with several microsatellite markers indicated that this patient had not inherited an allele from the father. A reduction in the hybridization signal was also observed when DNA from this patient was screened with cDNAs AE25, P5, B3A, and an extragenic marker EW206, clearly indicating hemizygosity at these loci. The combined evidence of dosage reduction and biparental inheritance with DNA marker EW301 indictates that this patient has a deletion of paternal origin rather than uniparental disomy. Pulsed-field gel electrophoresis has not, so far, revealed any evidence of an altered band pattern; however, studies are continuing. FISH analysis is currently in progress using YACs and cosmids to define the extent of this deletion.
- OSTI ID:
- 134226
- Report Number(s):
- CONF-941009--
- Journal Information:
- American Journal of Human Genetics, Journal Name: American Journal of Human Genetics Journal Issue: Suppl.3 Vol. 55; ISSN AJHGAG; ISSN 0002-9297
- Country of Publication:
- United States
- Language:
- English
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