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Clonal Origin of Tumor Cells in a Plexiform Neurofibroma with LOH in NF1 Intron 38 and in Dermal Neurofibromas without LOH of the NF1 Gene

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Abstract

LOH at the NF1 locus was investigated in 38 neurofibromas of 26 NF1 patients. Only in one of these tumors LOH was observed. In this plexiform neurofibroma of a NF1 patient with a constitutional one base-pair insertion in NF1 exon 4b, a non-random X-inactivation pattern was found, strongly suggesting a clonal origin of the tumor cells. The analysis of X-inactivation patterns allowed the classification of some of the other neurofibromas with regard to the detectability of clonal LOH. In 3 of 6 neurofibromas without LOH amenable to this analysis, a comparable X-inactivation pattern was found in constitutional and neurofibroma derived DNA. A clonal LOH would not have been detected in these tumors. However, we observed a nonrandom pattern in 3 of the 6 neurofibromas, suggesting a clonal origin of the tumor cells. LOH was not detected in these tumors, but could, however, have occurred by mutational events below the level of large somatic deletions, loss of a whole chromosome 17 or somatic recombination.

References (22)

  • R.E. Gale et al.

    Blood

    (1994)
  • S.M. Huson et al.

    The Neurofibromatoses, a Pathogenetic and Clinical Overview

    (1994)
  • W. Xu et al.

    Genes Chrom Cancer

    (1992)
  • E. Legius et al.

    Nat. Genet.

    (1993)
  • K.M. Shannon et al.

    N. Engl. J. Med.

    (1994)
  • G. Bollag et al.

    Nat Genet

    (1996)
  • A.G.J. Knudson

    Proc. Natl. Acad. Sci. USA

    (1971)
  • S.D. Colman et al.

    Nat. Genet.

    (1995)
  • S. Sawada et al.

    Nat Genet

    (1996)
  • P.J. Fialkow et al.

    N. Engl. J. Med.

    (1971)
There are more references available in the full text version of this article.

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