Confirmation of proximal 1q duplication using fluorescence in situ hybridization

Abstract

We report on a boy with excessively wrinkled skin, mild micro/brachycephaly with mild hydrocephalus and slightly small temporal lobes, apparently low-set ears, retro/micrognathia and cleft soft palate (Pierre-Robin anomaly), patent ductus arteriosus and foramen ovale, pulmonary hypoplasia, eventration of the left hemidiaphragm, right cryptorchidism, a sacral dimple, flexion contractures of fingers and knees, and equinovarus deformities of both feet. The infant had a de novo dir dup(1)(pter-->q25::q12-->qter). Partial duplications involving proximal 1q have rarely been reported. Furthermore, this is the first case of proximal duplication of chromosome 1q with unequivocal identification using fluorescence in situ hybridization (FISH) with a chromosome 1 painting probe.

Duplication Dup(1)(q32q44) Detected by Comparative Genomic Hybridization (CGH): Further Delineation of Trisomies 1q

“…The neuropathologic basis for severe mental retardation remains unclear. Hydrocephalic dilatation of the lateral ventricle was diagnosed on CT scan or at autopsy in 7 individuals of groups I-III [15,19,21,22,25,26,29]. In two infants of group I the cerebellum was hypoplastic [14,19] and anomalies of the gyral pattern, optic tract and absence of the olfactory nerves were noted in two children from group II and III on autopsy [18,21].…”

“…Patients were classified in different groups according to their cytogenetic data ( fig. 4): Group I comprises three patients with proximal duplications 1q11/12→q22-25 [14,22,25]. Group II consists of 10 patients with duplicated segments involving the intermediate chromosomal region 1q25→q31-41, six from three families with interstitial duplications distal to band 25 [5,7,10,18] and four from three families with duplications distal to band 1q31 [6,15,27].…”

De novo interstitial direct duplication 1(q23.1q31.1) in a fetus with Pierre Robin sequence and camptodactyly

“…Watson et al [1990] noted hydrocephalus with hypoplastic cerebellum, micrognathia, microstomia, microtia, microphthalmia, narrow palate, shield-like chest, and camptodactyly in an infant with duplicated 1q21 to 1qter. PRS and¯exion of ®ngers were observed by Chen et al [1994] in an infant with a duplication 1q12q25. The common chromosomal region duplicated in these patients, including our case, in whom PRS and¯exion of ®ngers were observed, is the 1q25 segment.…”

“…In clinical genetics, the precise identi®cation of the origin of the additional or missing chromosomal material is a key factor when considering genotypephenotype correlations, and ultimately may lead to the discovery of the genes responsible for the clinical abnormalities that present in such patients. To better de®ne the aberration, FISH analysis has to be performed, and only seven cases of partial trisomy 1q were analyzed using this method [Chen et al, 1994;Dupont et al, 1994;Mewar et al, 1994;Duba et al, 1997;Schorry et al, 1998;Sillen et al, 1998;Fan et al, 1999]. Duplication 1q syndromes can only be de®ned when several cases with a FISH-veri®ed partial trisomy 1q as the sole chromosomal aberration are investigated and in which the breakpoints are identi®ed [Sillen et al, 1998].…”

Boy with an interstitial 1q (q31q41) duplication confirmed by fluorescent in situ hybridisation

“…When a duplicated region is small it can be difficult to trace the origin of the extra segment. To better define the aberration, FISH analysis has to be performed and only four cases of partial trisomy 1q were analysed by this method [Chen et al, 1994 ;Duba et al, 1997;DuPont et al, 1994;Mewar et al, 1994]. Only when several cases with a FISH-verified partial trisomy 1q as the sole chromosomal aberration have been investigated and in which the breakpoints are identified can duplication 1q syndromes be defined.…”