"Partial trisomy 22 and 11" due to a paternal 11;22 translocation associated with Hirschsprung disease

Trisomy 22 Mosaicism from Prenatal to Postnatal Findings: A Case Series and Systematic Review of the Literature

BACKGROUND

Among aneuploidies compatible with life, trisomy 22 mosaicism is extremely rare, and only about 25 postnatal and 18 prenatal cases have been described in the literature so far. The condition is mainly characterized by facial and body asymmetry, cardiac heart defects, facial dysmorphisms, growth failure, delayed puberty, and variable degrees of neurodevelopmental delay.

PROBLEM

The scattered information regarding the condition and the dearth of data on its natural history and developmental outcomes restrict genetic counseling, particularly in prenatal settings. Moreover, a prompt diagnosis is frequently delayed by the negative selection of trisomic cells in blood, with mosaicism percentage varying among tissues, which often entails the need for further testing. Purpose/topic: The aim of our work is to provide assistance in prenatal and postnatal genetic counseling by systematically delineating the current knowledge of the condition. This entails defining the prenatal and postnatal characteristics of the condition and presenting novel data from three cases, both prenatally and postnatally. Additionally, we report the developmental outcomes observed in two new patients.

Chromosomal and related Mendelian syndromes associated with Hirschsprung's disease

Hirschsprung's disease (HSCR) is a fairly frequent cause of intestinal obstruction in children. It is characterized as a sex-linked heterogonous disorder with variable severity and incomplete penetrance giving rise to a variable pattern of inheritance. Although Hirschsprung's disease occurs as an isolated phenotype in at least 70% of cases, it is not infrequently associated with a number of congenital abnormalities and associated syndromes, demonstrating a spectrum of congenital anomalies. Certain of these syndromic phenotypes have been linked to distinct genetic sites, indicating underlying genetic associations of the disease and probable gene-gene interaction, in its pathogenesis. These associations with HSCR include Down's syndrome and other chromosomal anomalies, Waardenburg syndrome and other Dominant sensorineural deafness, the Congenital Central Hypoventilation and Mowat-Wilson and other brain-related syndromes, as well as the MEN2 and other tumour associations. A number of other autosomal recessive syndromes include the Shah-Waardenburg, the Bardet-Biedl and Cartilage-hair hypoplasia, Goldberg-Shprintzen syndromes and other syndromes related to cholesterol and fat metabolism among others. The genetics of Hirschsprung's disease are highly complex with the majority of known genetic sites relating to the main susceptibility pathways (RET an EDNRB). Non-syndromic non-familial, short-segment HSCR appears to represent a non-Mendelian condition with variable expression and sex-dependent penetrance. Syndromic and familial forms, on the other hand, have complex patterns of inheritance and being reported as autosomal dominant, recessive and polygenic patterns of inheritance. The phenotypic variability and incomplete penetrance observed in Hirschsprung's disease could also be explained by the involvement of modifier genes, especially in its syndromic forms. In this review, we look at the chromosomal and Mendelian associations and their underlying signalling pathways, to obtain a better understanding of the pathogenetic mechanisms involved in developing aganglionosis of the distal bowel.

Mosaic trisomy 22 associated with total colonic aganglionosis and malrotation

AIMS

Abnormalities of chromosome 22 karyotype have been reported to be associated with both malrotation and aganglionosis. However, although malrotation has been reported to occur in the rare mosaic trisomy 22, Hirschsprung's disease has not. We present a case of mosaic trisomy 22 that presented during the neonatal period with malrotation and total colonic aganglionosis, and we discuss the possible pathogenesis of both conditions in the light of this rare genetic abnormality. The association of total colonic aganglionosis and mosaic trisomy 22 has not previously been reported.

RESULTS

A male neonate with an antenatal diagnosis of de novo mosaic trisomy 22 underwent a laparotomy with correction of malrotation and midgut volvulus on day 3 of life. Rectal biopsy was performed because he had not passed meconium. This revealed Hirschsprung's disease; an ileostomy was formed, and histology confirmed aganglionosis as far as the terminal ileum. At 6 months, a modified Lester Martin Duhamel pull-through was performed. He is showing normal development at follow-up.

CONCLUSIONS

We recommend an increased index of suspicion of Hirschsprung's disease and malrotation in patients with mosaic trisomy 22 until further evidence can establish or exclude a meaningful relationship.

Phenotypic expansion of the supernumerary derivative (22) chromosome syndrome: VACTERL and Hirschsprung's disease

Phenotypically healthy carriers of the balanced 11;22 translocation, the most frequent non-Robertsonian constitutional translocation known in human beings, are at risk of having a progeny with supernumerary derivative (22)t(11;22) syndrome [der(22) syndrome]. We present the cases of 2 male patients with supernumerary der(22) syndrome [47,XY,+der(22)t(11;22)(q23;q11.2)mat], yielding partial trisomy for 22pter-q11 and 11q23-qter. These cases expand the phenotype of the der(22) syndrome, with the first case highlighting the phenotypic overlap of VACTERL and the second adding Hirschsprung's disease and intestinal malrotation to the list of associated anorectal anomalies. Because der(22) syndrome and cat eye syndrome (partial tetrasomy of 22q11) share a similar region of extra dosage on 22q11 and both typically manifest an anorectal phenotype, a dosage-sensitive gene for anorectal anomalies may be present in this locus.

Anesthesia in a patient with chromosome 11;22 translocation: a case report and literature review

Chromosome 11;22 translocation is a rare genetic condition, which results in characteristic features some of which may present problems when these children require surgery and anesthesia. We describe a child with this chromosomal variant who presented for surgery and anesthesia. The case report and review of the literature is presented here.

Genetic aspects of Hirschsprung's disease

Hirschsprung's disease (HD) is a relatively common cause of intestinal obstruction in the newborn, characterized by the absence of autonomic ganglion cells in the terminal bowel. Existence of familial cases indicates that genetic factors may be involved in the etiology of some cases of HD. Different inheritance patterns observed in subsets of HD families or kindreds, and the detection of different chromosome aberrations in some HD patients, suggest genetic heterogeneity of HD. Recent expansion of molecular genetics has identified multiple susceptibility genes of HD. These include the RET gene, the glial cell-derived neurotrophic factor gene, the endothelin-B receptor gene, and endothelin-3 gene. Furthermore, some other genes or genetic factors are speculated to be implicated in the development of HD, and it is believed that multiple factors play a role in disease development in some cases. Taken together, these data suggest and may explain the complexity of the etiology of HD. This review focuses on recent advances in our understanding of the genetic aspects of HD.

Trisomy 22 confirmed by fluorescent in situ hybridization

We report on a newborn girl with multiple congenital anomalies, whose G-banded chromosome analysis showed complete trisomy 22. Chromosome painting using a whole-chromosome painting probe for chromosome 22 confirmed that neither chromosome 22 was involved in a cryptic translocation.

A case of Hirschsprung disease with a chromosome 13 microdeletion, del(13)(q32.3q33.2): potential mapping of one disease locus

A mentally retarded boy with discrete physical findings, Hirschsprung disease (HD) and a microdeletion of 13q,del(13)(q32.3q33.2) is described. Band 13q33.1 was consistently missing in all cells. There have been, to date, 4 published cases of deletions involving the long arm of chromosome 13 associated with HD: the interstitial deletion reported here is much smaller than, and it partially overlaps with, the previously reported deletions; it could be helpful for mapping one of the genes involved in this disease.

Partial trisomy 22 with Dandy-Walker malformation

Partial trisomy 22 usually occurs through a 3:1 meiotic segregation of the parental 11q;22q translocation carrier, which is the most common balanced translocation in man. Common neurologic findings are delayed psychomotor development and muscular hypotonia. There have been a few neuroradiologic and neuropathologic studies, which include ventricular dilatation, arrhinencephaly, and aplasia or hypoplasia of the cerebellar vermis, corpus callosum and pons. We here add one patient with partial trisomy 22 who had, in addition to the usual features, Dandy-Walker malformation, which, to our knowledge, is a previously undescribed feature.

The Kaufman-McKusick syndrome: another association

A male infant with features of the Kaufman-McKusick syndrome and a previously unstated association with Hirschsprung's disease is described.