Omphalocele and partial trisomy 1q syndrome

Distal partial trisomy 1q: report of two cases and a review of the literature

We report on two cases with partial trisomy 1q syndrome. One case was a mid-trimester fetus with multiple malformations that was prenatally diagnosed with a de novo distal partial trisomy 1q. Prenatal ultrasound at 24th gestational week demonstrated the presence of cleft lip and palate, increased biparietal diameter and decreased abdominal circumference. Cytogenetic analysis (GTG banding) and subsequent fluorescence in situ hybridization (FISH) using whole chromosome paint 1 and multicolor banding (MCB) demonstrated an aberrant karyotype 46,XY,dup(1)(q31q43 approximately 44). The second case was a newborn male infant with multiple congenital malformations. He had a derivative chromosome 18 as a result of a maternal insertion involving chromosomes 1 and 18. Further analyses including MCB showed his karyotype as 46,XY,ins(18;1)(q22;q23q31.1 approximately 32). The present cases and a review of the literature suggest that partial trisomy of the long arm of chromosome 1 is a distinct clinical entity.

Chromosomal Abnormalities Associated With Omphalocele

Fetuses with omphalocele have an increased risk for chromosomal abnormalities. The risk varies with maternal age, gestational age at diagnosis, association with umbilical cord cysts, complexity of associated anomalies, and the contents of omphalocele. There is considerable evidence that genetics contributes to the etiology of omphalocele. This article provides an overview of chromosomal abnormalities associated with omphalocele and a comprehensive review of associated full aneuploidy such as trisomy 18, trisomy 13, triploidy, trisomy 21, 45,X, 47,XXY, and 47,XXX, partial aneuploidy such as dup (3q), dup (11p), inv (11), dup (1q), del (1q), dup (4q), dup (5p), dup (6q), del (9p), dup (15q), dup(17q), Pallister-Killian syndrome with mosaic tetrasomy 12p and Miller-Dieker lissencephaly syndrome with deletion of 17p13.3, and uniparental disomy (UPD) such as UPD 11 and UPD 14. Omphalocele is a prominent marker for chromosomal abnormalities. Perinatal identification of omphalocele should alert chromosomal abnormalities and familial unbalanced translocations, and prompt thorough cytogenetic investigations and genetic counseling.

Omphalocele in trisomy 3q: further delineation of phenotype

We report a case of a patient with omphalocele, dysmorphic features, and mild developmental delay associated with a chromosomal aberration. Chromosome studies showed that the propositus carries a maternally derived unbalanced translocation der(4)t(3;4)(q27.3;q32.3), resulting in trisomy for region 3q27.3-->qter and monosomy for 4q32.3-->qter. Because the association between dup3q and omphalocele has been reported in several cases, we analyzed the data on 93 previously reported patients with partial trisomy of the long arm of chromosome 3 and compared the clinical features between the cases. The imbalance of chromosome 3 in the patient was further defined by fluorescence in situ hybridization (FISH) studies using bacterial artificial chromosome (BAC) clones. BAC clone RP11-171N2 was identified as a breakpoint-spanning clone in the patient and his mother. Based on our comparative analysis, we have delineated that the smallest region of overlap (SRO) associated with omphalocele is from BAC 171N2 to 3qter. We hypothesize that the SRO contains a gene(s) important in normal abdominal wall development and is of potential interest for further investigation.

Partial 1q and 21p trisomies in a male child due to maternal t(1;21)

Proband 7 years old male child referred for cytogenetic investigation revealed 47, XY + der (21), t(1;21) (q32;q11) mat.

Anterior segment dysgenesis and congenital glaucoma associated with partial trisomy of chromosome 1 (1q32-qter)

A child born with partial trisomy of chromosome 1 (1q32-qter) survived and was seen for anterior segment dysgenesis and congenital glaucoma. Pure trisomy 1q is rarely seen in live-born infants and has not previously been described in association with congenital glaucoma. The genetic basis for glaucoma is complicated and multifactorial and probably determined by a number of genes on a variety of chromosomes. The current case provides some evidence that part of chromosome 1 may be involved with the etiology of a glaucomatous process.

Partial duplication of 3q and distal deletion of 11q in a stillbirth with an omphalocele containing the liver, short limbs, and intrauterine growth retardation

We describe a female stillbirth with duplication of 3q21-->qter and deletion of 11q23-->qter resulting from an unbalanced segregation of a maternal t(3;11) reciprocal translocation. The proband had some of the clinical features consistent with those seen in patients with dup(3q) syndrome or distal del(11q) syndrome. Prenatal sonographic examination showed short limbs, intrauterine growth retardation, and an omphalocele containing the liver.

Prenatal diagnosis of partial trisomy 1q using fluorescent in situ hybridization

We report the use of fluorescent in situ hybridization (FISH) with a DNA library of chromosome 1-specific probes to confirm the karyotype, 46,XY,15+der15,t(1;15)(q32.1; q26.3), obtained by prenatal periumbilical blood sampling from a fetus who exhibited multiple abnormalities by ultrasound examination. GTG-banding of chromosomes obtained from the mother showed a normal karyotype, while the father was unavailable for study. The propositus was born at 37 weeks gestation and survived for several weeks. Cytogenetic analysis performed after the birth of the male infant with multiple anomalies verified partial trisomy 1q. This patient is compared with other partial trisomy 1q patients reported in the literature. The usefulness of FISH is demonstrated in situations where fetal abnormalities are present with de novo chromosomal rearrangements where paternal chromosomes are unavailable for study.

Congenital ocular defects associated with an abnormality of the human chromosome 1: trisomy 1q32-qter

This article describes the detailed ocular pathology found in a premature neonate, born at 34 weeks, with multiple congenital anomalies resulting from de novo trisomy 1q32-qter. The ocular defects include goniodysgenesis, persistent tunica vasculosa lentis and hyaloid vessels, hypopigmentation of the posterior iris epithelium, ectopia of the ciliary processes, and abnormal insertion of the ciliary muscle and cataract. This is the first report of the detailed ocular pathology in a case of trisomy 1q and is also unusual in that the chromosomal defect has apparently arisen de novo in the proband.

Duplication of the distal part of the long arm of chromosome 1

A case of dup(1)(q42----qter) is reported. A literature review of duplication of the distal third of chromosome 1 with breakpoints at various sites, 1q23, 1q25, 1q32, and 1q42, was undertaken. Clinical similarities and differences based on the size of the duplicated segment and other associated deficiencies are summarized.

Partial duplication 1q: report of four patients and review of the literature

Here we report on 4 unrelated patients with reciprocal translocations which resulted in duplication of the distal portion of chromosome 1q. Although the patients had certain non-specific malformations in common, our investigation and a review of the literature do not suggest the existence of a distinct phenotype due to this chromosome abnormality. We think that the coexisting deletion present in each of these patients is responsible for most of the observed differences in clinical manifestations. The variable phenotype makes clinical recognition difficult and precludes making a long-term prognosis.

Apparent Fryns syndrome in a boy with a tandem duplication of 1q24-31.2

We report on a newborn boy with manifestations of Fryns syndrome who also had a mosaic tandem duplication of chromosome 1q24-31.2. The child had a diaphragmatic hernia, cleft palate, hypoplastic and absent digits, micrognathia, long philtrum, thin upper lip, and anteverted nose. The baby died at age 5 hours. An autopsy demonstrated absent right middle lobe of the lung, bilateral renal cysts, hypoplastic renal arteries, urethral stricture, hydronephrosis, and aortic coarctation. The brain was abnormal with absent olfactory tracts and cerebral and cerebellar heterotopias. This is the first report of a chromosome anomaly in a child with Fryns phenotype. It suggests that the gene for Fryns syndrome may be located in the region 1q24-31.2.

Clinical variability of partial duplication 1q: a clinical report and literature review

A female baby with multiple congenital malformations was born to a father previously known as a carrier of reciprocal translocation, t(1;18)(q25;p11). Her chromosome constitution was 46,XX,-18,der18,t(1;18)(q25;p11)pat, namely, partial duplication 1q25----qter. The main manifestations were: macrocephaly, hirsutism, camptodactyly, eye defects, lymphedema, and duodenal atresia. This patient illustrates the phenotype variability expected from such a large duplication of chromosome 1.

Coloboma and microphthalmos in chromosomal aberrations. Chromosomal aberrations and neural crest cell developmental field

A survey of more than 500 reports on patients with autosomal chromosomal aberrations associated with microphthalmos and/or coloboma shows that these anomalies are unspecific. Anterior chamber anomalies were common as were abnormal ears, preauricular pits and tags, cleft lip-palate, micrognathia, urogenital malformations, congenital heart disease, atresia of the anus and minor malformations of the hands and feet. It is proposed that the chromosomal aberrations induce faulty development of neural crest cells and rostral neural plate derivatives.