Interstitial deletion 5p accompanied by dicentric ring formation of the deleted segment resulting in trisomy 5p13-cen

Abstract

Karyotypes with an interstitial deletion and a marker chromosome formed from the deleted segment are rare. We identified such a rearrangement in a newborn infant, who presented with macrocephaly, asymmetric square skull, minor facial anomalies, omphalocele, inguinal hernias, hypospadias, and club feet. The karyotype 46,XY,del(5) (pter→p13::cen→qter)/47,XY, + dicr(5)(:p13→cen::p13→cen), del(5)(pter→p13::cen→qter) was identified by banding studies and FISH analysis in the peripheral lymphocytes. One breakpoint on the del(5) maps distal to GDNF, and FISH analysis using an α‐satellite probe suggests that the proximal break‐point maps within the centromere. The dicentric r(5) consists of two copies of the segment deleted in the del(5), resulting in trisomy of proximal 5p (5p13‐cen). The phenotype of the propositus is compared with other trisomy 5p cases and possible mechanisms for the generation of this unique chromosomal rearrangement are discussed. © 1996 Wiley‐Liss, Inc.

Cancer-associated alteration of pericentromeric heterochromatin may contribute to chromosome instability

“…The ring 5 chromosome, formed from a deletion within the cen-5p13 region (Schuffenhauer et al, 1996), retained D5Z2 ( Figure 1c) and has a kinetochore (Supplementary Figure S2). These findings are consistent with D5Z1 representing a chromosome arm sequence outside of the functional centromere.…”

“…HME5cdk4, HME50hTERT and HME50TR cells were grown in supplemented MCDB 171 medium (Invitrogen, Carslbad, CA, USA) (Ramirez et al, 2003). BF lymphoblastoid cells were grown in RPMI1640 medium/15% FBS and have the designation 47,XY, del(5)(p10p13), þ r(5)(p10p13) (Schuffenhauer et al, 1996). HeLa and HT1080 cell lines were obtained from ATCC (Manassas, VA, USA).…”

Omphalocele in trisomy 3q: further delineation of phenotype

“…The most common aneuploidies associated with omphalocele are trisomy 18 and 13, Turner syndrome (45, X), and triploidy. Various other chromosomal abnormalities have been found in newborns and fetuses with omphalocele, including rearrangements of 1q (19, 20), 5p (21, 22), partial trisomy 6q (23), and in Miller–Dieker syndrome (MIM #247200) due to 17p deletion (24–26). Here, we present the case of an 11‐month‐old boy with omphalocele who has a duplication of 3q27.3‐qter due to the malsegregation of a maternal t(3;4)(q27.3;q32.3) but does not show the BDLS or dup3q phenotype.…”

Modification of CMT1 Phenotypes by the Independent Coexisting Neurogenetic Disorders, McArdle Disease and Chromosome 5p Trisomy

“…Fifty cases of complete or partial duplication have been reported. 4–7 CNS features include hypotonia, seizures, and psychomotor retardation. Craniofacial hallmarks are macroscaphocephaly, micrognathia, macroglossia, low‐set ears, upslanting palpebral fissures, epicanthus, hypertelorism, and depressed nasal bridge.…”

“…Duplication of the 5p11→p13 region seems necessary and largely sufficient for the full phenotype, whereas shorter or distal (5p14→pter) duplications result in fewer and milder anomalies. 5–7…”