A ring chromosome 3 and a 47th chromosome formed by the portions of 3p and 3q distal to the r(3) breakpoints were found in a girl with mental retardation and minor facial anomalies. The supernumerary chromosome 3, rea(3), had a primary constriction inside its 3p portion (3p23) and was consistently stable both in lymphocytes and fibroblasts. In situ hybridization with alphoid probes revealed that the r(3) maintained its wild-type-centromere, whereas the rea(3) showed no alphoid-related signals. This case and a similar one recently reported demonstrate that acentric fragments can acquire a new centromere and become stable, and that supernumerary marker chromosomes can also originate by the junction of the acentric portions distal to the centric region forming a ring. The possibility of such a chromosome segregating will depend on its ability to (re)activate a new centromere.

A novel mechanism for the origin of supernumerary chromosomes

ROCCHI, Mariano;
1996-01-01

Abstract

A ring chromosome 3 and a 47th chromosome formed by the portions of 3p and 3q distal to the r(3) breakpoints were found in a girl with mental retardation and minor facial anomalies. The supernumerary chromosome 3, rea(3), had a primary constriction inside its 3p portion (3p23) and was consistently stable both in lymphocytes and fibroblasts. In situ hybridization with alphoid probes revealed that the r(3) maintained its wild-type-centromere, whereas the rea(3) showed no alphoid-related signals. This case and a similar one recently reported demonstrate that acentric fragments can acquire a new centromere and become stable, and that supernumerary marker chromosomes can also originate by the junction of the acentric portions distal to the centric region forming a ring. The possibility of such a chromosome segregating will depend on its ability to (re)activate a new centromere.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11586/25479
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 19
  • ???jsp.display-item.citation.isi??? 18
social impact