OBJECTIVE: To explore the genetic basis for a girl with distinctive facial features, epilepsy, intellectual disability, chronic constipation and hypopigmentation of neck and upper extremities. METHODS: Whole exome sequencing was carried out for the proband. Candidate variant was verified by Sanger sequencing. RESULTS: The proband was found to harbor a heterozygous nonsense c.586G>T (p.Glu196*) variant of the ZEB2 gene, which was unreported previously. The variant was not detected in either parent. CONCLUSION The ZEB2 gene c.586G>T (p.Glu196*) variant probably underlay the Mowat-Wilson syndrome in this patient. Hypopigmentation in the neck and upper extremities may be related to Mowat-Wilson syndrome. Prenatal diagnosis was recommended for subsequent pregnancies.
Facies ; Female ; Hirschsprung Disease ; Humans ; Hypopigmentation ; Intellectual Disability/genetics* ; Microcephaly ; Pregnancy ; Zinc Finger E-box Binding Homeobox 2/genetics*

OBJECTIVE: To explore the genetic basis of three children with unexplained mental retardation/developmental delay. METHODS: Peripheral venous blood samples were collected for routine G-banding karyotyping analysis and chromosomal microarray analysis (CMA). Whole exome sequencing (WES) was also carried out for patient 3. RESULTS: The karyotypes of the 3 children were normal. The result of CMA analysis of patient 1 was arr[GRCh37]: 2q22/3(145 128 071-145 159 029)×1, with a 31 kb deletion, which was predicted to be a pathogenic copy number variation. The deletion has involved exons 8 to 10 of the ZEB2 gene. Patient 2 was arr[hg19]:2q22.3 (145 071 457-146 881 759)×1, with a 1.81 Mb deletion involving the ZEB2 and GTDC1 genes. Patient 3 was arr[GRCh37]: 9p23p23(11 698 261-12 106 261)×1, with a 408 kb deletion containing no disease-associated gene. WES has identified a c.2102C>A (p.Ser701*) variant in exon 8 of the ZEB2 gene, which was included in ClinVar database and rated as pathogenic, and verified by Sanger sequencing as a de novo variant. CONCLUSION For the substantial clinical and genetic heterogeneity of Mowat-Wilson-syndrome, CMA and WES are helpful to identify the etiology of children with developmental delay/mental retardation of unknown causes, particularly those with peculiar facial features and multiple congenital malformations.
Child ; DNA Copy Number Variations ; Facies ; Glycosyltransferases/genetics* ; Hirschsprung Disease ; Humans ; Intellectual Disability/genetics* ; Microcephaly/genetics*

OBJECTIVE: To identify pathogenic variants in two patients with suspected for Mowat-Wilson syndrome (MWS). METHODS: Genomic DNA was extracted from peripheral blood samples of the patients and his family members, and gene variants were analysis by Trio-whole exome sequences and copy number variation sequencing. RESULTS: Patient 1 was found to carried a de novo heterozygous c.2769C>A (p.Y923*) nonsense variant of ZEB2 gene. The variant was not found in his healthy parents and sister. Patient 2 carried a de novo heterozygous frameshift variant of the ZEB2 gene, namely c.315delC (p.A105Afs*3), which has not been previously reported. Both variants were predicted to be pathogenic and can lead to premature occurrence of stop codons. CONCLUSION The heterozygous c.2769C>A (p.Y923*) and c.315delC (p.A105Afs*3) variants of the ZEB2 gene probably underlay the pathogenesis in the two patients. Gene testing has facilitated confirmation of the diagnosis and genetic counselling.
DNA Copy Number Variations ; Facies ; Hirschsprung Disease ; Humans ; Intellectual Disability/genetics* ; Microcephaly/genetics* ; Zinc Finger E-box Binding Homeobox 2/genetics*

OBJECTIVE: To summarize the clinical phenotype and genotype of a Chinese child affected with Mowat-Wilson syndrome (MWS). METHODS: Clinical data of the patient were collected. The patient was analyzed by whole-exome sequencing (WES) as well as Sanger sequencing. RESULTS: The patient was a male infant with recurrent fever and slow growth. He also had characteristic facies, recurrent spasm, and growth retardation. WES revealed that he has carried a heterozygous nonsense c.2609C>G (p.Ser870X) variant of the ZEB2 gene (30% mosaicism). Based on the American College of Medical Genetics and Genomics standards and guidelines, the variant was predicted to be pathogenic (PVS1+PS1+PS2+PM2). CONCLUSION The c.2609C>G variant of the ZEB2 gene probably underlay the MWS in this child. The mosaicism of the variant may explain his mild symptoms.
Child ; Facies ; Hirschsprung Disease/genetics* ; Humans ; Infant ; Intellectual Disability/genetics* ; Male ; Microcephaly/genetics* ; Mutation

OBJECTIVE: To explore the genetic basis of a proband with distinctive facial features, global developmental delay, seizures and hypoplasia of corpus callosum through next generation sequencing (NGS). METHODS: Genomic DNA was extracted from peripheral blood samples of the proband and his family members. Whole exome and flanking sequences were screened by NGS. Suspected variants were verified by Sanger sequencing. RESULTS: The proband was found to carry a heterozygous c.2824G>T (p.G942X) variant of the ZEB2 gene, which was verified by Sanger sequencing to be a de novo variant. CONCLUSION The heterozygous c.2824G>T (p.G942X) variant of the ZEB2 gene probably underlies the Mowat-Wilson syndrome in the proband.
Facies ; Genetic Variation ; Heterozygote ; Hirschsprung Disease ; genetics ; Humans ; Intellectual Disability ; genetics ; Microcephaly ; genetics ; Whole Exome Sequencing ; Zinc Finger E-box Binding Homeobox 2 ; genetics

OBJECTIVE: To study the expression levels of glial cell line-derived neurotrophic factor family receptor α-1 (GFRα1) and enhancer of zeste homolog 2 (EZH2) in the intestinal tissue of children with Hirschsprung's disease (HSCR), as well as the role of EZH2 in the regulation of GFRα1 gene expression and the pathogenesis of HSCR. METHODS: The samples of colon tissue with spasm from 24 children with HSCR after radical treatment of HSCR were selected as the experimental group, and the samples of necrotized colon tissue from 18 children with neonatal necrotizing enterocolitis after surgical resection were selected as the control group. Real-time PCR and Western blot were used to measure the expression levels of GFRα1 and EZH2 in colon tissue in both groups. Human neuroblastoma SH-SY5Y cells were divided into an EZH2 over-expression group and a negative control group. The cells in the EZH2 over-expression group were transfected with pCMV6-EZH2 plasmid, and those in the negative control group were transfected with pCMV6 plasmid. The expression levels of EZH2 and GFRα1 were measured after transfection. RESULTS: Compared with the control group, the experimental group had significant reductions in the mRNA and protein expression levels of GFRα1 and EZH2 in colon tissue (P<0.05), and the protein expression of EZH2 was positively correlated with that of GFRα1 (r=0.606, P=0.002). Compared with the negative control group, the EZH2 over-expression group had significant increases in the expression levels of EZH2 and GFRα1 after SH-SY5Y cells were transfected with EZH2 over-expression plasmid (P<0.05). CONCLUSIONS Low expression of EZH2 in the colon tissue of children with HSCR may be one of the causes of inadequate expression of GFRα1 and onset of HSCR.
Child ; Colon ; Enhancer of Zeste Homolog 2 Protein ; genetics ; Glial Cell Line-Derived Neurotrophic Factor Receptors ; genetics ; Hirschsprung Disease ; genetics ; Humans ; Infant, Newborn ; RNA, Messenger

Hirschsprung′s disease (HSCR) is one of the major causes of chronic incomplete intestinal obstruction in children. HSCR is considered a type of neurocristopathy caused by no colonization of ganglion cells on some parts of the bowel wall due to abnormal termination of the migration of vagal neural cells during embryonic development. This disease can be classified into different types according to the length of the affected intestinal canal. Most HSCR patients present with single deformity, but some HSCR patients are affected by other deformities, which constitutes syndromic HSCR, such as congenital central hypoventilation syndrome, Fryns syndrome, and cartilage-hair hypoplasia syndrome. Most syndromes have abnormal genetic material. An adequate knowledge of syndromic HSCR is of vital importance for accurate diagnosis and prognostic evaluation. This article reviews the clinical manifestations, genetic basis, and genetic modes of different types of syndromic HSCR.
Hirschsprung Disease ; classification ; complications ; genetics ; Humans ; Syndrome

Congenital central hypoventilation syndrome with Hirschsprung's disease, also known as Haddad syndrome, is an extremely rare disorder with variable symptoms. Recent studies described that congenital central hypoventilation syndrome had deep relation to the mutation of the PHOX2B gene in its diagnosis and phenotype. We report a newborn male infant with clinical manifestations of recurrent hypoventilation with hypercapnea and bowel obstruction. These clinical manifestations were compatible with congenital central hypoventilation syndrome and Hirschsprung's disease, and polyalanine 26 repeats in the PHOX2B gene supported the diagnosis of congenital central hypoventilation. We described a first case of Haddad syndrome in Korean and its clinical and genetic characteristics were discussed.
Asian Continental Ancestry Group ; Base Sequence ; DNA Mutational Analysis ; Hirschsprung Disease/diagnosis/genetics/pathology ; Homeodomain Proteins/*genetics ; Humans ; Hypoventilation/congenital/diagnosis/genetics ; Infant, Newborn ; Male ; Molecular Sequence Data ; *Mutation ; Sleep Apnea, Central/diagnosis/genetics ; Transcription Factors/*genetics

OBJECTIVETo investigate the expression of Notch-1 and Jagged-2 in the normal and spastic segments of colon in patients with Hirschsprung disease(HD), and to explore the correlation of Notch-1 and Jagged-2 with pathogenesis of HD.

METHODSFrom 2005 to 2010, resected colon specimens of 30 cases with HD were selected for this study. Normal colonic segments were served as control group, while the transitional and spastic segments as experimental group. Immunohistochemical staining, Western blotting, and RT-PCR were applied to detect the expression of Notch-1 and Jagged-2.

RESULTSA large number of Notch-1 and Jagged-2 positive gangliocytes were observed in the control group, while none was observed in spastic segments. Significantly less Notch-1 and Jagged-2 positive gangliocytes were found in the transitional segments. Western blotting revealed that Notch-1 and Jagged-2 protein levels in spastic segments (0.19±0.02 and 0.13±0.04) were less than that in transitional segments and normal segments (0.58±0.05 and 0.52±0.04, 0.72±0.04 and 0.69±0.04, respectively)(P<0.05). RT-PCR revealed that Notch-1 and Jagged-2 mRNA levels were consistent with protein expression.

CONCLUSIONNotch-1 and Jagged-2 are not expressed in spastic colon segments, which may be associated with the pathogenesis of HD.

Case-Control Studies ; Female ; Hirschsprung Disease ; genetics ; metabolism ; Humans ; Infant ; Intercellular Signaling Peptides and Proteins ; genetics ; Jagged-2 Protein ; Male ; Membrane Proteins ; genetics ; RNA, Messenger ; genetics ; Receptor, Notch1 ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction

OBJECTIVETo explore the relationship between exon 3 mutation in the methyl CpG-binding protein 2 (MeCP2-E3) gene and Hirschsprung disease (HSCR) and anorectal malformations (ARMs).

METHODSPCR and DNA sequencing were used to detect the mutation of MeCP2-E3 in 120 healthy controls, 120 HSCR, and 50 ARMs.

RESULTSOn sequencing, 45(37.5%) children with HSCR had basic replacement in MeCP2-E3, 12(10.0%) of them were homozygous mutation. Fourteen(28.0%) children with ARMs had basic replacement in MeCP2-E3, 4(8%) of them were homozygous mutation. There were no mutation in the control group.

CONCLUSIONSMutation of MeCP2-E3 is present in the peripheral blood of children with HSCR or ARMs, which may contribute to the development of Hirschsprung disease or anorectal malformations.

Anorectal Malformations ; Anus, Imperforate ; genetics ; Case-Control Studies ; Child, Preschool ; Exons ; Female ; Hirschsprung Disease ; genetics ; Humans ; Male ; Methyl-CpG-Binding Protein 2 ; genetics ; Mutation ; Phenotype