A patient with Edwards syndrome caused by a rare pseudodicentric chromosome 18 of paternal origin

Abstract

We present an unusual case of trisomy 18 due to a pseudodicentric chromosome 18 of paternal origin. The karyotype was: 46,XY,—18, + psu dic(18)(qter→cen→p11.31::p11.31→psucen→qter). The origin of the abnormal chromosome was verified by FISH with a painting probe from chromosome 18. Absence of short‐arm telomeres was shown by multicolor FISH, and the results of DNA analysis showed monosomy for loci D18S59 and D18S170 as well as paternal inheritance of the aberrant chromosome. The child's phenotype was characteristic of trisomy 18.

The human brain and face: mechanisms of cranial, neurological and facial development revealed through malformations of holoprosencephaly, cyclopia and aberrations in chromosome 18

“…; Gravholt et al. ), and rarer still are cases involving both T18 and the presentation of cyclopia with HPE (Lang et al. ; Floore et al.…”

The dark side of centromeres: types, causes and consequences of structural abnormalities implicating centromeric DNA

“…This high incidence correlated to the presence of rearrangements compatible with chromothripsis observed on the Roberstonian chromosome 161 . Other types of pseudodicentric chromosomes are Non-ROBs (in 85% of the cases involving one acrocentric chromosome) and are associated with several syndromes such as Kabuki syndrome, a genetic disorder with multiple congenital anomalies, intellectual disability, and growth deficiency 162 , Edward syndrome, a trisomy of chromosome 18 163 and isodicentric X [i(X)] or Y [i(Y)] chromosomes such as Turner syndrome (as described in the paragraph “Centromere breaks and disease”).…”

Aramid‐short‐fiber reinforced rubber as a tire tread composite

“…The phenotype is in the majority of cases described as very similar to trisomy 18 or Edward's syndrome. Isochromosome 18q appears in the classical form with one centromere and two q arms and have been described in about 20 cases [Van Dyke, 1988 for review of cases before 1988; Chen et al, 1998 for review of cases after 1988], as double isochromosomes together with i(18p) described in four cases [Muller et al, 1972; Larson et al, 1978; Romain et al, 1992; van den Berg et al, 1999], and as a pseudodicentric chromosome with two centromeres separated by p arm material [Laurent et al, 1978; Madan et al, 1981; Ward et al, 1981; Fioretti et al, 1982; Wulfsberg et al, 1984; Meguid and Habibian, 1992; Brandt et al, 1994; Levy‐Mozziconacci et al, 1996; Gravholt et al, 1997] or q arm material [Floore et al, 1989; Bryke et al, 1990; Fujiwara et al, 1992; Ausems et al, 1994]. Isochromosomes are mirror duplications as they are composed of genetically identical arms.…”

“…Both cases were of maternal origin. The parental origin of a pseudodicentric chromosome 18q has been determined in two cases using a limited number of PCR‐based DNA polymorphisms [Brandt et al, 1994; Gravholt et al, 1997].…”