9q34 loss of heterozygosity in a tuberous sclerosis astrocytoma suggests a growth suppressor-like activity also for the TSC1 gene

Caterina Carbonara, Lucia Longa, Enrico Grosso, Carla Borrone, Maria Grazia Garrè, Massimo Brisigotti, Nicola Migone

Research output: Contribution to journalArticle


Tuberous sclerosis is an autosomal dominant disease whose characteristic feature is the development of multiple hamartomas in a variety of organs and tissues. Two major loci have been identified so far: TSC1 on chromosome 9q34 and TSC2 on chromosome 16p13.3. Loss of heterozygosity at 16p13.3 associated markers has been recently observed in hamartomatous lesions of some tuberous sclerosis patients. Here we report the first evidence of loss of heterozygosity at the TSC1 critical region in a giant cell astrocytoma of a familial tuberous sclerosis case. Segregation analysis showed that the 9q34 haplotype lost carried the putative normal TSC1 gene. These data support the hypothesis of both a germline and somatic loss-of function mutation for the development of tuberous sclerosis hamartomas and suggest a tumor-suppressor-like activity also for the TSC1 gene product. Finally, the possible significance of a second small region of loss of heterozygosity at 9p21, found in the same astrocytoma, is discussed.

Original languageEnglish
Pages (from-to)1829-1832
Number of pages4
JournalHuman Molecular Genetics
Issue number10
Publication statusPublished - Oct 1994


ASJC Scopus subject areas

  • Genetics
  • Statistics, Probability and Uncertainty
  • Applied Mathematics
  • Public Health, Environmental and Occupational Health
  • Molecular Biology
  • Genetics(clinical)

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