Mosaic Type-1 NF1 Microdeletions as a Cause of Both Generalized and Segmental Neurofibromatosis Type-1 (NF1)
Por:
Messiaen, L, Vogt, J, Bengesser, K, Fu, CH, Mikhail, F, Serra, E, Garcia-Linares, C, Cooper, DN, Lazaro, C and Kehrer-Sawatzki, H
Publicada:
1 feb 2011
Resumen:
Mosaicism is an important feature of type-1 neurofibromatosis (NF1) on account of its impact upon both clinical manifestations and transmission risk. Using FISH and MLPA to screen 3500 NF1 patients, we identified 146 individuals harboring gross NF1 deletions, 14 of whom (9.6%) displayed somatic mosaicism. The high rate of mosaicism in patients with NF1 deletions supports the postulated idea of a direct relationship between the high new mutation rate in this cancer predisposition syndrome and the frequency of mosaicism. Seven of the 14 mosaic NF1 deletions were type-2, whereas four were putatively type-1, and three were atypical. Two of the four probable type-1 deletions were confirmed as such by breakpoint-spanning PCR or SNP analysis. Both deletions were associated with a generalized manifestation of NF1. Independently, we identified a third patient with a mosaic type-1 NF1 deletion who exhibited segmental NF1. Together, these three cases constitute the first proven mosaic type-1 deletions so far reported. In two of these three mosaic type-1 deletions, the breakpoints were located within PRS1 and PRS2, previously identified as hotspots for nonallelic homologous recombination (NAHR) during meiosis. Hence, NAHR within PRS1 and PRS2 is not confined to meiosis but may also occur during postzygotic mitotic cell cycles. Hum Mutat 32:213-219, 2011. (C) 2011 Wiley-Liss, Inc.
Filiaciones:
Messiaen, L:
Univ Alabama Birmingham, Dept Genet, Med Genom Lab, Birmingham, AL USA
Vogt, J:
Univ Ulm, Inst Human Genet, D-89081 Ulm, Germany
Bengesser, K:
Univ Ulm, Inst Human Genet, D-89081 Ulm, Germany
Fu, CH:
Univ Alabama Birmingham, Dept Genet, Med Genom Lab, Birmingham, AL USA
Mikhail, F:
Univ Alabama Birmingham, Dept Genet, Med Genom Lab, Birmingham, AL USA
:
IMPPC, Barcelona, Spain
Garcia-Linares, C:
IMPPC, Barcelona, Spain
Cooper, DN:
Cardiff Univ, Sch Med, Inst Med Genet, Cardiff, S Glam, Wales
Lazaro, C:
Inst Invest Biomed Bellvitge IDIBELL, Inst Catala Oncol, Lab Recerca Translac, Unitat Diagnost Mol,Programa Canc Hereditari, Barcelona, Spain
Kehrer-Sawatzki, H:
Univ Ulm, Inst Human Genet, D-89081 Ulm, Germany
Green Submitted, gold
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