Analysis of sporadic tuberous sclerosis patients with the TSC2 cDNA reveals several gene rearrangements and deletions
- Massachusetts General Hospital, Boston, MA (United States); and others
Tuberous sclerosis (TSC) is an autosomal dominant disorder characterized by hamartomas and hamartias in many organs including brain, skin, heart and kidneys. Two TSC genes have been localized through linkage analysis, TSC1 to 9q34 and TSC2 to 16p13.3. TSC2 was recently cloned. The distribution of sporadic TSC patients between TSC1 and TSC2 is at present unknown, but tests of genetic heterogeneity in families suggest that each is equally represented. Genetic heterogeneity may account for some of the variation in clinical expression; however, there is no evidence at present to support differences in clinical phenotypes between the 2 genetic loci. With the isolation of the TSC2 gene we have commenced mutation studies of our familial and sporadic TSC patients. Thus far six chromosome 16-linked families have been screened with the TSC2 cDNA and no detectable changes were observed using Southern analysis. In addition, 85 sporadic TSC patients were analyzed by Southern analysis. Using multiple restriction digests, nine patients revealed altered patterns, including three patients that appeared to have complete deletions. RT-PCR was performed on these patients confirming that the TSC2 gene was deleted. However, the remaining patients showed normal patterns, indicating that they either have TSC1 mutations or they possess more subtle small deletions or point mutations. At present we are designing an SSCP-based approach to determine the nature of the mutations in our 16 linked TSC families.
- OSTI ID:
- 134779
- 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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