FISH characterisation of dynamic mosaicism involving an inv dup(15) in a patient with mental retardation.
We report on a man with mental retardation and a complex karyotype with cells containing up to three morphologically distinct supernumerary marker chromosomes (SMCs) in most metaphases. Fluorescence in situ hybridisation studies using chromosome 15-specific probes characterised the presence of seven SMCs all derived from chromosome 15. The results suggest that the patient originally had a large inv dup(15) containing two copies of the Prader-Willi/Angelman critical region which became mitotically unstable, and by a process of dynamic mosaicism various morphologically distinct SMCs arose.
Cockwell
A E
AE
Wessex Regional Genetics Laboratory, Salisbury District Hospital, Salisbury, Wiltshire, SP2 8BJ, UK. wessex.genetics@dial.pipex.com
Dávalos
I P
IP
Rivera
H R
HR
Crolla
J A
JA
D000328:Adult; D017204:Angelman Syndrome / Q000175:diagnosis / Q000235:genetics*; D002869:Chromosome Aberrations; D007446:Chromosome Inversion; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D015342:DNA Probes / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008214:Lymphocytes; D008297:Male; D009030:Mosaicism / Q000175:diagnosis / Q000235:genetics*; D011218:Prader-Willi Syndrome / Q000175:diagnosis / Q000235:genetics*
D015342:DNA Probes