ABSTRACT
Calcium (Ca2+) is a universal second messenger involved in synaptogenesis and cell survival; consequently, its regulation is important for neurons. ATPase plasma membrane Ca2+ transporting 1 (ATP2B1) belongs to the family of ATP-driven calmodulin-dependent Ca2+ pumps that participate in the regulation of intracellular free Ca2+. Here, we clinically describe a cohort of 12 unrelated individuals with variants in ATP2B1 and an overlapping phenotype of mild to moderate global development delay. Additional common symptoms include autism, seizures, and distal limb abnormalities. Nine probands harbor missense variants, seven of which were in specific functional domains, and three individuals have nonsense variants. 3D structural protein modeling suggested that the variants have a destabilizing effect on the protein. We performed Ca2+ imaging after introducing all nine missense variants in transfected HEK293 cells and showed that all variants lead to a significant decrease in Ca2+ export capacity compared with the wild-type construct, thus proving their pathogenicity. Furthermore, we observed for the same variant set an incorrect intracellular localization of ATP2B1. The genetic findings and the overlapping phenotype of the probands as well as the functional analyses imply that de novo variants in ATP2B1 lead to a monogenic form of neurodevelopmental disorder.
Subject(s)
Intellectual Disability , Nervous System Malformations , Neurodevelopmental Disorders , HEK293 Cells , Humans , Intellectual Disability/diagnosis , Intellectual Disability/genetics , Mutation, Missense/genetics , Neurodevelopmental Disorders/genetics , Phenotype , Plasma Membrane Calcium-Transporting ATPases/geneticsABSTRACT
Pur-α protein (PURA) syndrome manifests in early childhood with core features such as neurodevelopmental and speech delay, feeding difficulties, epilepsy, and hypotonia at birth. We identified three cases with PURA syndrome in a cohort of patients with unexplained muscular weakness, presenting with a predominantly neuromuscular and ataxic phenotype. We further characterize the clinical presentation of PURA syndrome including myopathic facies and muscular weakness as the main clinical symptoms in combination with elevated serum creatine kinase levels. Furthermore, we report two novel variants located in the conservative domains PUR-I and PUR-II. For the first time, we present the muscle biopsies of PURA syndrome patients, showing myopathic changes, fiber size variability, and fast fiber atrophy as the key features. PURA syndrome should be taken into consideration as a differential diagnosis in pediatric patients with unexplained muscle weakness.
Subject(s)
Epilepsy , Intellectual Disability , Neuromuscular Diseases , Child , Child, Preschool , DNA-Binding Proteins/genetics , Epilepsy/genetics , Humans , Intellectual Disability/genetics , Neuromuscular Diseases/complications , Neuromuscular Diseases/diagnosis , Transcription Factors/geneticsABSTRACT
A male patient with mosaic paternal uniparental diploidy (PUD) is presented. After birth, the patient presented with hypoglycemia, hemihypertrophy, umbilical hernia, and hepatomegaly. Afterward pancreatic hypertrophy, liver hemangiomas, and cysts were detected sonographically. At the age of 3.5 months, hepatoblastoma was diagnosed. To investigate suspected Beckwith-Wiedemann syndrome (BWS), extensive genetic analyses were performed using DNA from chorionic villus sampling, amniocentesis, and peripheral blood lymphocytes (chromosome analysis, methylation-specific multiplex ligation-dependent probe amplification assays, microsatellite analyses, and single nucleotide polymorphism array analysis). These analyses led to the detection of mosaic PUD. In peripheral blood lymphocytes, a male cell line (46,XY[27]/46,XX[5]) predominated, suggesting a mixture of uniparental isodisomy and heterodisomy. The genetic analyses suggest that the mosaic PUD status was attributable to fertilization of an oocyte by two sperms, with subsequent triploidy rescue giving rise to haploidy, which in turn was rescued. Notably, in the majority of the 28 mosaic PUD patients reported to date, BWS was initially suspected. Mosaic PUD status is associated with a higher risk for a broad range of malignant and benign tumors than in BWS. As tumors can also occur after childhood surveillance into adolescence is indicated. Mosaic PUD must therefore be considered in patients with suspected BWS.
Subject(s)
Genetic Association Studies , Karyotype , Mosaicism , Paternal Inheritance , Uniparental Disomy , Genetic Association Studies/methods , Genetic Testing , Humans , Infant , Male , PhenotypeABSTRACT
Bladder exstrophy-epispadias complex (BEEC), the severe end of the urorectal malformation spectrum, has a profound impact on continence as well as sexual and renal functions. It is widely accepted that for the majority of cases the genetic basis appears to be multifactorial. Here, we report the first study which utilizes genome-wide association methods to analyze a cohort comprising patients presenting the most common BEEC form, classic bladder exstrophy (CBE), to identify common variation associated with risk for isolated CBE. We employed discovery and follow-up samples comprising 218 cases/865 controls and 78 trios in total, all of European descent. Our discovery sample identified a marker near SALL1, showing genome-wide significant association with CBE. However, analyses performed on follow-up samples did not add further support to these findings. We were also able to identify an association with CBE across our study samples (discovery: P = 8.88 × 10(-5); follow-up: P = 0.0025; combined: 1.09 × 10(-6)) in a highly conserved 32 kb intergenic region containing regulatory elements between WNT3 and WNT9B. Subsequent analyses in mice revealed expression for both genes in the genital region during stages relevant to the development of CBE in humans. Unfortunately, we were not able to replicate the suggestive signal for WNT3 and WNT9B in a sample that was enriched for non-CBE BEEC cases (P = 0.51). Our suggestive findings support the hypothesis that larger samples are warranted to identify association of common variation with CBE.
Subject(s)
Bladder Exstrophy/genetics , Wnt Proteins/genetics , Wnt Proteins/metabolism , Wnt3 Protein/genetics , Wnt3 Protein/metabolism , Animals , Base Sequence , Bladder Exstrophy/pathology , Case-Control Studies , Conserved Sequence , Genetic Predisposition to Disease , Genitalia/embryology , Genitalia/metabolism , Genome-Wide Association Study , Humans , Mice , Polymorphism, Single Nucleotide , Transcription Factors/genetics , White People/geneticsABSTRACT
BACKGROUND: Anorectal malformations (ARM) have a prevalence of around 1 in 2500 live births. In around 50% of patients, the malformation is isolated, while in the remainder it arises within the context of complex genetic abnormalities or a defined genetic syndrome. Recent studies have implicated rare copy number variations (CNVs) in both isolated and nonisolated ARM, and identified plausible candidate genes. METHODS: In the present study, array-based molecular karyotyping was performed to identify causative CNVs in 32 sporadic ARM patients with comorbid abnormalities of the central nervous system (CNS). This phenotype was selected to enrich for rare CNVs, since previous research has implicated rare CNVs in both CNS abnormalities and ARM. RESULTS: In five patients, a probable disease-causing CNV was identified (del6q14.3q16.3, del14q32.2, del17q12q21.2, and two patients with del22q11.21). In three of these patients, the CNVs were de novo. For the remaining two patients, no parental DNA was available. Deletions at 22q11.21 and 6q14.3 have been associated with both CNS abnormalities and ARM. In contrast, deletions at 14q32.2 have only been described in patients with CNS abnormalities, and the del17q12q21.2 is a novel CNV. Expression studies in mice suggest that NEUROD2 and RARA, which reside within the newly identified del17q12q21.2 region, are candidate genes for the formation of microcephaly and ARM. CONCLUSION: The present data suggest that CNVs are a frequent cause of the ARM with CNS abnormalities phenotype, and that array-analysis is indicated in such patients.
Subject(s)
Abnormalities, Multiple/genetics , Anal Canal/abnormalities , Anus, Imperforate/genetics , Central Nervous System/abnormalities , Chromosome Deletion , DNA Copy Number Variations/genetics , Rectum/abnormalities , Abnormalities, Multiple/pathology , Adolescent , Anal Canal/pathology , Anorectal Malformations , Anus, Imperforate/pathology , Child , Chromosome Mapping/methods , Female , Haplotypes/genetics , Humans , Karyotyping , Male , Rectum/pathology , Young AdultABSTRACT
Congenital abnormalities of the kidney and urinary tract (CAKUT) account for approximately half of children with chronic kidney disease and they are the most frequent cause of end-stage renal disease in children in the US. However, its genetic etiology remains mostly elusive. VACTERL association is a rare disorder that involves congenital abnormalities in multiple organs including the kidney and urinary tract in up to 60% of the cases. By homozygosity mapping and whole-exome resequencing combined with high-throughput mutation analysis by array-based multiplex PCR and next-generation sequencing, we identified recessive mutations in the gene TNF receptor-associated protein 1 (TRAP1) in two families with isolated CAKUT and three families with VACTERL association. TRAP1 is a heat-shock protein 90-related mitochondrial chaperone possibly involved in antiapoptotic and endoplasmic reticulum stress signaling. Trap1 is expressed in renal epithelia of developing mouse kidney E13.5 and in the kidney of adult rats, most prominently in proximal tubules and in thick medullary ascending limbs of Henle's loop. Thus, we identified mutations in TRAP1 as highly likely causing CAKUT or VACTERL association with CAKUT.
Subject(s)
Anal Canal/abnormalities , DNA Mutational Analysis , Esophagus/abnormalities , Exosomes , Genetic Testing , HSP90 Heat-Shock Proteins , Heart Defects, Congenital/genetics , Kidney/abnormalities , Limb Deformities, Congenital/genetics , Mutation , Spine/abnormalities , Trachea/abnormalities , Vesico-Ureteral Reflux/genetics , Age Factors , Animals , DNA Mutational Analysis/methods , Europe , Female , Gene Expression Regulation, Developmental , Genetic Predisposition to Disease , Genetic Testing/methods , Gestational Age , HSP90 Heat-Shock Proteins/genetics , HSP90 Heat-Shock Proteins/metabolism , Heart Defects, Congenital/diagnosis , High-Throughput Nucleotide Sequencing , Homozygote , Humans , Kidney/embryology , Kidney/metabolism , Limb Deformities, Congenital/diagnosis , Male , Mice , Multiplex Polymerase Chain Reaction , Pedigree , Predictive Value of Tests , Risk Factors , United States , Urogenital Abnormalities , Vesico-Ureteral Reflux/diagnosisABSTRACT
BACKGROUND: Classic bladder exstrophy (CBE) is the most common form of the bladder exstrophy and epispadias complex. Previously, we and others have identified four patients with a duplication of 22q11.21 among a total of 96 unrelated CBE patients. METHODS: Here, we investigated whether this chromosomal aberration was commonly associated with CBE/bladder exstrophy and epispadias complex in an extended case-control sample. Multiplex ligation-dependent probe amplification and microarray-based analysis were used to identify 22q11.21 duplications in 244 unrelated bladder exstrophy and epispadias complex patients (including 217 CBE patients) and 665 healthy controls. RESULTS: New duplications of variable size were identified in four CBE patients and one control. Pooling of our previous and present data (eight duplications in 313 CBE patients) yielded a combined odds ratio of 31.86 (95% confidence interval, 4.24-1407.97). Array-based sequence capture and high-throughput targeted re-sequencing established that all breakpoints resided within the low-copy repeats 22A to 22D. Comparison of the eight duplications revealed a 414 kb phenocritical region harboring 12 validated RefSeq genes. Characterization of these 12 candidate genes through whole-mount in situ hybridization of mouse embryos at embryonic day 9.5 suggested that CRKL, THAP7, and LZTR1 are CBE candidate genes. CONCLUSION: Our data suggest that duplication of 22q11.21 increases CBE risk and implicate a phenocritical region in disease formation.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Bladder Exstrophy/genetics , Chromosomal Proteins, Non-Histone/genetics , Chromosome Duplication , Chromosomes, Human, Pair 22 , Epispadias/genetics , Nuclear Proteins/genetics , Transcription Factors/genetics , Animals , Bladder Exstrophy/pathology , Case-Control Studies , Embryo, Mammalian , Epispadias/pathology , Female , Humans , In Situ Hybridization , Male , Mice , Odds Ratio , Oligonucleotide Array Sequence Analysis , Sequence Analysis, DNA , Urethra/abnormalities , Urethra/metabolism , Urinary Bladder/abnormalities , Urinary Bladder/metabolismABSTRACT
BACKGROUND: The acronym VATER/VACTERL association describes the combination of at least three of the following cardinal features: vertebral defects, anorectal malformations, cardiac defects, tracheoesophageal fistula with or without esophageal atresia, renal malformations, and limb defects. Although fibroblast growth factor-8 (FGF8) mutations have mainly found in patients with Kallmann syndrome, mice with a hypomorphic Fgf8 allele or complete gene invalidation display, aside from gonadotropin-releasing hormone deficiency, parts or even the entire spectrum of human VATER/VACTERL association. METHODS: We performed FGF8 gene analysis in 49 patients with VATER/VACTERL association and 27 patients presenting with a VATER/VACTERL-like phenotype (two cardinal features). RESULTS: We identified two heterozygous FGF8 mutations in patients displaying either VATER/VACTERL association (p.Gly29_Arg34dup) or a VATER/VACTERL-like phenotype (p.Pro26Leu) without limb anomalies. Whereas the duplication mutation has not been reported before, p.Pro26Leu was once observed in a Kallmann syndrome patient. Both our patients had additional bilateral cryptorchidism, a key phenotypic feature in males with FGF8 associated Kallmann syndrome. Each mutation was paternally inherited. Besides delayed puberty in both and additional unilateral cryptorchidism in one of the fathers, they were otherwise healthy. Serum hormone levels downstream the gonadotropin-releasing hormone in both patients and their fathers were within normal range. CONCLUSION: Our results suggest FGF8 mutations to contribute to the formation of the VATER/VACTERL association. Further studies are needed to support this observation.
Subject(s)
Anal Canal/abnormalities , Cryptorchidism/genetics , Esophagus/abnormalities , Fibroblast Growth Factor 8/genetics , Heart Defects, Congenital/genetics , Kidney/abnormalities , Limb Deformities, Congenital/genetics , Mutation/genetics , Spine/abnormalities , Trachea/abnormalities , Anti-Mullerian Hormone/blood , Base Sequence , DNA Primers/genetics , Enzyme-Linked Immunosorbent Assay , Follicle Stimulating Hormone/blood , Gene Components , Germany , Heterozygote , Humans , Inhibins/blood , Luteinizing Hormone/blood , Male , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , Testosterone/bloodABSTRACT
Anorectal malformations (ARMs) comprise a broad spectrum of conditions ranging from mild anal anomalies to complex cloacal malformations. In 40-50% of cases, ARM occurs within the context of defined genetic syndromes or complex multiple congenital anomalies, such as VATER/VACTERL (vertebral defects [V], ARMs [A], cardiac defects [C], tracheoesophageal fistula with or without esophageal atresia [TE], renal malformations [R], and limb defects [L]) association. Here, we report the identification of deletions at chromosome 13q using single nucleotide polymorphism-based array analysis in two patients with mild ARM as part of VATER/VACTERL and VATER/VACTERL-like associations. Both deletions overlap the previously defined critical region for ARM. Heterozygous Efnb2 murine knockout models presenting with mild ARM suggest EFNB2 as an excellent candidate gene in this region. Our patients showed a mild ARM phenotype, closely resembling that of the mouse. We performed a comprehensive mutation analysis of the EFNB2 gene in 331 patients with isolated ARM, or ARM as part of VATER/VACTERL or VATER/VACTERL-like associations. However, we did not identify any disease-causing mutations. Given the convincing argument for EFNB2 as a candidate gene for ARM, analyses of larger samples and screening of functionally relevant non-coding regions of EFNB2 are warranted. In conclusion, our report underlines the association of chromosome 13q deletions with ARM, suggesting that routine molecular diagnostic workup should include the search for these deletions. Despite the negative results of our mutation screening, we still consider EFNB2 an excellent candidate gene for contributing to the development of ARM in humans.
Subject(s)
Anus, Imperforate/genetics , Anus, Imperforate/physiopathology , Chromosome Disorders/genetics , Ephrin-B2/genetics , Esophagus/abnormalities , Heart Defects, Congenital/physiopathology , Radius/abnormalities , Spine/abnormalities , Trachea/abnormalities , Animals , Anorectal Malformations , Anus, Imperforate/complications , Child, Preschool , Chromosome Deletion , Chromosomes, Human, Pair 13/genetics , Disease Models, Animal , Esophagus/physiopathology , Female , Heart Defects, Congenital/complications , Heart Defects, Congenital/genetics , Humans , Infant, Newborn , Limb Deformities, Congenital/genetics , Limb Deformities, Congenital/physiopathology , Male , Mice , Mice, Knockout , Mutation , Radius/physiopathology , Spine/physiopathology , Trachea/physiopathologyABSTRACT
BACKGROUND: Esophageal atresia with/without trachea-esophageal fistula (EA/TEF) denotes a spectrum of severe congenital malformations. The aim of this systematic study was to determine both the recurrence risk for EA/TEF, and the risk for malformations of the VATER/VACTERL association spectrum, in first-degree relatives of patients with isolated EA/TEF. METHODS: A total of 108 unrelated patients with isolated EA/TEF were included. These individuals had 410 first-degree relatives including 194 siblings. The presence of EA/TEF and malformations of the VATER/VACTERL association spectrum in relatives was systematically assessed. Data from the EUROCAT network were used for comparison. RESULTS: None of the first-degree relatives displayed any form of EA/TEF. In two families, a first-degree relative presented with malformations from the VATER/VACTERL association spectrum. However, no increase in the risk for malformations of the VATER/VACTERL association spectrum was found compared with the control cohort (p = 0.87). In three families, one more distantly related relative presented with EA/TEF. CONCLUSION: In contrast to previous studies, our results suggest a very low recurrence risk for isolated EA/TEF and/or for malformations of the VATER/VACTERL association spectrum among first-degree relatives.
Subject(s)
Anal Canal/abnormalities , Anus, Imperforate/pathology , Esophageal Atresia/pathology , Esophagus/abnormalities , Heart Defects, Congenital/pathology , Kidney/abnormalities , Limb Deformities, Congenital/pathology , Radius/abnormalities , Spine/abnormalities , Trachea/abnormalities , Tracheoesophageal Fistula/pathology , Adolescent , Adult , Anal Canal/pathology , Anus, Imperforate/genetics , Case-Control Studies , Child , Esophageal Atresia/complications , Esophageal Atresia/genetics , Esophagus/pathology , Female , Heart Defects, Congenital/genetics , Humans , Inheritance Patterns , Kidney/pathology , Limb Deformities, Congenital/genetics , Male , Pedigree , Radius/pathology , Risk , Siblings , Spine/pathology , Trachea/pathology , Tracheoesophageal Fistula/complications , Tracheoesophageal Fistula/geneticsABSTRACT
BACKGROUND: The exstrophy-epispadias complex (BEEC) is a urogenital birth defect of varying severity. The causes of the BEEC are likely to be heterogeneous, with individual environmental or genetic risk factors still being largely unknown. In this study, we aimed to identify de novo causative copy number variations (CNVs) that contribute to the BEEC. METHODS: Array-based molecular karyotyping was performed to screen 110 individuals with BEEC. Promising CNVs were tested for de novo occurrence by investigating parental DNAs. Genes located in regions of rearrangements were prioritized through expression analysis in mice to be sequenced in the complete cohort, to identify high-penetrance mutations involving small sequence changes. RESULTS: A de novo 0.9 Mb microduplication involving chromosomal region 19p13.12 was identified in a single patient. This region harbors 20 validated RefSeq genes, and in situ hybridization data showed specific expression of the Wiz gene in regions surrounding the cloaca and the rectum between GD 9.5 and 13.5. Sanger sequencing of the complete cohort did not reveal any pathogenic alterations affecting the coding region of WIZ. CONCLUSIONS: The present study suggests chromosomal region 19p13.12 as possibly involved in the development of CBE, but further studies are needed to prove a causal relation. The spatiotemporal expression patterns determined for the genes encompassed suggest a role for Wiz in the development of the phenotype. Our mutation screening, however, could not confirm that WIZ mutations are a frequent cause of CBE, although rare mutations might be detectable in larger patient samples. 19p13.12, microduplication, bladder exstrophy-epispadias complex, array-based molecular karyotyping, in situ hybridization analysis, copy number variations, WIZ gene.
Subject(s)
Bladder Exstrophy/genetics , Chromosome Duplication , Chromosomes, Human, Pair 19/genetics , DNA Copy Number Variations , Animals , Base Sequence , Gene Dosage , Gene Duplication , Humans , Karyotype , Mice , Sequence Analysis, DNA , Urinary Bladder/abnormalitiesABSTRACT
Early post-twinning mutational events can account for discordant phenotypes in monozygotic (MZ) twin pairs. Such mutational events may comprise genomic alterations of different sizes, ranging from single nucleotides to large copy-number variations (CNVs). Anorectal malformations (ARM) and the bladder exstrophy-epispadias complex (BEEC) represent the most severe end of the urorectal malformation spectrum. Recently, CNV studies in patients with sporadic ARM and the BEEC have identified de novo events that occur in specific chromosomal regions. We hypothesized that early arising, post-twinning CNVs might contribute to discordance in MZ twin pairs with ARM or the BEEC; knowledge of such CNVs might help to identify additional chromosomal regions involved in the development of these malformations. We investigated four discordant MZ twin pairs (three ARM and one BEEC) using molecular karyotyping arrays comprising 1,140,419 markers with a median marker spacing of 1.5 kb. Filtering the coding regions for possible disease-causing post-twinning de novo CNVs present only in the affected twin, but not in the unaffected twin or the parents, identified a total of 136 CNVs. These 136 CNVs were then filtered against publicly available databases and finally re-evaluated visually. No potentially causative CNV remained after applying these filter criteria. Our results suggest that post-twinning CNV events that affect coding regions of the genome did not contribute to the discordant phenotypes in MZ twin pairs that we investigated. Possible causes for the discordant phenotypes include changes in regulatory elements or smaller genetic changes within coding regions which may be detectable by whole-exome sequencing.
Subject(s)
Anus, Imperforate/genetics , Bladder Exstrophy/genetics , DNA Copy Number Variations/genetics , Diseases in Twins/genetics , Twins, Monozygotic/genetics , Adolescent , Anorectal Malformations , Child , Child, Preschool , Comparative Genomic Hybridization , DNA/genetics , Humans , Infant, Newborn , Male , Phenotype , Real-Time Polymerase Chain ReactionABSTRACT
BACKGROUND: RAB11B was described previously once with a severe form of intellectual disability. We aim at validation and delineation of the role of RAB11B in neurodevelopmental disorders. METHODS: We present seven novel individuals with disease-associated variants in RAB11B when compared with the six cases described in the literature. We performed a cross-sectional analysis to identify the clinical spectrum and the core phenotype. Additionally, structural effects of the variants were assessed by molecular modeling. RESULTS: Seven distinct de novo missense variants were identified, three of them recurrent (p.(Gly21Arg), p.(Val22Met), and p.(Ala68Thr)). Molecular modeling suggests that those variants either affect the nucleotide binding (at amino acid positions 21, 22, 33, 68) or the interaction with effector molecules (at positions 72 and 75). Our data confirmed the main manifestations as neurodevelopmental disorder with intellectual disability (85%), muscular hypotonia (83%), structural brain anomalies (77%), and visual impairment (70%). Combined analysis indicates a genotype-phenotype correlation; variants impacting the nucleotide binding cause a severe phenotype with intellectual disability, and variants outside the binding pocket lead to a milder phenotype with epilepsy. CONCLUSIONS: We confirm that disease-associated missense variants in RAB11B cause a neurodevelopmental disorder and suggest a genotype-phenotype correlation based on the impact on nucleotide binding functionality of RAB11B.
ABSTRACT
BACKGROUND: Isolated esophageal atresia (EA) is a rare congenital malformation whose etiology remains largely unknown. Nine twin pairs with EA were identified from our clinical service, prompting the performance of a systematic review of the literature and the first reported twin study of isolated EA. METHODS: A total of 330 twin pairs with EA were identified from the literature. The zygosity, concordance, and malformation (isolated vs. nonisolated) status of all 339 twin pairs were evaluated. A total of 72 twin pairs (4 of 9 / 68 of 330) fulfilled the criteria for inclusion in a classic twin study of isolated EA. RESULTS: The pairwise concordance rates were 50% (95% confidence interval [CI], 34-66%) for monozygous (MZ) twin pairs and 26% (95% CI, 15-42%) for dizygous (DZ) twin pairs (p = 0.033). The probandwise concordance rates were 67% (95% CI, 53-78%) for MZ twin pairs and 42% (95% CI, 29-56%) for DZ twin pairs (p = 0.011). The MZ/DZ ratios were 1.9 for pairwise analysis and 1.6 for probandwise analysis. The familial risk ratios for MZ and DZ twin pairs were 1700 and 900, respectively. CONCLUSION: The observation of higher concordance rates for MZ compared to DZ twin pairs indicates that genetic factors contribute to isolated EA.
Subject(s)
Diseases in Twins/genetics , Esophageal Atresia/genetics , Genetic Predisposition to Disease , Twins, Dizygotic/genetics , Twins, Monozygotic/genetics , Diseases in Twins/epidemiology , Diseases in Twins/etiology , Female , Humans , MaleABSTRACT
The acronym VATER/VACTERL association is used to describe the non-random co-occurrence of vertebral defects (V), anorectal malformations (A), cardiac defects (C), tracheo-esophageal fistula with or without esophageal atresia (TE), renal malformations (R), and limb defects (L). We report a familial case of VATER/VACTERL association in which both the index case and her maternal uncle displayed four major component features of the disorder. A systematic literature search identified 12 previously described familial cases. However, on comparison, both members fulfilled the diagnostic criteria for VATER/VACTERL association only in one instance, and ours is the second such report. Although, a SNP array-based analysis identified no causal genomic alteration, the findings in the present family suggest that genetic factors are implicated in the development of the disorder.
Subject(s)
Abnormalities, Multiple/diagnosis , Anus, Imperforate/diagnosis , Heart Defects, Congenital/diagnosis , Limb Deformities, Congenital/diagnosis , Abnormalities, Multiple/genetics , Anal Canal/abnormalities , Anus, Imperforate/genetics , Esophagus/abnormalities , Female , Genetic Predisposition to Disease/genetics , Heart Defects, Congenital/genetics , Humans , Kidney/abnormalities , Limb Deformities, Congenital/genetics , Male , Polymorphism, Single Nucleotide , Radius/abnormalities , Spine/abnormalities , Trachea/abnormalitiesABSTRACT
PURPOSE: To determine the anorectal function in patients with anorectal malformations (ARM) in order to facilitate patient counseling and follow-up. METHODS: Data were collected by the German network for urorectal malformations (CURE-Net) according to the International Krickenbeck consensus. Questionnaires on bowel function and a defecation protocol were completed by the families/patients. The clinical findings were assessed from the patients' clinical records. RESULTS: Two hundred and ninety-seven patients with ARM were assessed, 175 patients gave complete data on continence, 52 of them were excluded due to mental retardation, age, and earlier type of pullthrough. Complete continence was found in 27 %, perineal fistula in 40 %, rectourethral/vesical in 10 %, vestibular in 24 %, cloaca in 0 %. Krickenbeck grade 1 soiling: 42 %, grade 2 and 3: 31 %. Forty-nine percent of the incontinent patients practiced bowel management, reaching continence in 19 %. The statement of constipation (67 %) was validated with the last clinical findings, showing coprostasis in 46 %, "Not suffering constipation" was confirmed in 61 % and falsified in 29 %. CONCLUSION: ARM patients in Germany, as assessed by independent researchers, show a high rate of fecal incontinence and insufficiently treated constipation. Parents should be counseled accordingly and motivated to engage in consequent follow-up. Intensified efforts in the conservative treatment of constipation and fecal incontinence are crucial to improvement.
Subject(s)
Anus, Imperforate/surgery , Fecal Incontinence/surgery , Adolescent , Adult , Anal Canal/abnormalities , Anal Canal/surgery , Anorectal Malformations , Anus, Imperforate/diagnosis , Child , Child, Preschool , Female , Germany , Humans , Male , Middle Aged , Rectum/abnormalities , Rectum/surgery , Registries , Surveys and Questionnaires , Young AdultABSTRACT
VATER/VACTERL association refers to the non-random co-occurrence of the following component features: vertebral defects, anal atresia, cardiac malformations, tracheoesophageal atresia, renal abnormalities, and limb defects. Recently, Solomon et al. (Hum Genet 127:731-733, 2010) observed an increased prevalence of component features among first-degree relatives of VATER/VACTERL patients suggesting that in some patients, the disorder may be inherited. To replicate these findings, we investigated 87 VATER/VACTERL patients with the presence of a minimum of three component features and their first-degree relatives (n = 271). No increase in the overall prevalence of component features was observed in first-degree relatives compared to the general population (χ² = 2.68, p = 0.10). Separate analysis for the prevalence of single component features showed a higher prevalence of tracheoesophageal fistula/atresia among first-degree relatives compared to the general population (OR 17.65, 95% CI 2.47-126.05). However, this was based on occurrence in one family only. Our findings suggest that although familial occurrence renders a genetic contribution likely, the overall risk of recurrence among the first-degree relatives of patients with VATER/VACTERL association is probably very low. Since the patients in the present study were young and no offspring could be studied, estimation of the role of de novo mutations in the development of VATER/VACTERL was not possible.
Subject(s)
Abnormalities, Multiple/epidemiology , Anus, Imperforate/epidemiology , Genetic Predisposition to Disease/epidemiology , Heart Defects, Congenital/epidemiology , Limb Deformities, Congenital/epidemiology , Anal Canal/abnormalities , Cohort Studies , Esophagus/abnormalities , Europe , Female , Humans , Infant , Kidney/abnormalities , Male , Odds Ratio , Prevalence , Radius/abnormalities , Spine/abnormalities , Trachea/abnormalitiesABSTRACT
BACKGROUND: Goltz syndrome (GS) is a X-linked disorder defined by defects of mesodermal- and ectodermal-derived structures and caused by PORCN mutations. Features include striated skin-pigmentation, ocular and skeletal malformations and supernumerary or hypoplastic nipples. Generally, GS is associated with in utero lethality in males and most of the reported male patients show mosaicism (only three non-mosaic surviving males have been described so far). Also, precise descriptions of neurological deficits in GS are rare and less severe phenotypes might not only be caused by mosaicism but also by less pathogenic mutations suggesting the need of a molecular genetics and functional work-up of these rare variants. RESULTS: We report two cases: one girl suffering from typical skin and skeletal abnormalities, developmental delay, microcephaly, thin corpus callosum, periventricular gliosis and drug-resistant epilepsy caused by a PORCN nonsense-mutation (c.283C > T, p.Arg95Ter). Presence of these combined neurological features indicates that CNS-vulnerability might be a guiding symptom in the diagnosis of GS patients. The other patient is a boy with a supernumerary nipple and skeletal anomalies but also, developmental delay, microcephaly, cerebral atrophy with delayed myelination and drug-resistant epilepsy as predominant features. Skin abnormalities were not observed. Genotyping revealed a novel PORCN missense-mutation (c.847G > C, p.Asp283His) absent in the Genome Aggregation Database (gnomAD) but also identified in his asymptomatic mother. Given that non-random X-chromosome inactivation was excluded in the mother, fibroblasts of the index had been analyzed for PORCN protein-abundance and -distribution, vulnerability against additional ER-stress burden as well as for protein secretion revealing changes. CONCLUSIONS: Our combined findings may suggest incomplete penetrance for the p.Asp283His variant and provide novel insights into the molecular etiology of GS by adding impaired ER-function and altered protein secretion to the list of pathophysiological processes resulting in the clinical manifestation of GS.
Subject(s)
Acyltransferases , Focal Dermal Hypoplasia , Membrane Proteins , Acyltransferases/genetics , Female , Focal Dermal Hypoplasia/complications , Focal Dermal Hypoplasia/genetics , Focal Dermal Hypoplasia/pathology , Humans , Male , Membrane Proteins/genetics , Mutation , PhenotypeABSTRACT
OBJECTIVE: To identify genetic and nongenetic risk factors that contribute to the severity of the bladder exstrophy-epispadias complex (BEEC). STUDY DESIGN: Patients with BEEC from North America (n = 167) and Europe (n = 274) were included. The following data were collected: associated anomalies, parental age at conception, mode of conception, periconceptional folic acid supplementation, maternal risk factors during pregnancy, and environmental risk factors. The patients were divided into 3 subgroups according to phenotype severity: (i) mild, epispadias (n = 43); (ii) intermediate, classic bladder exstrophy (n = 366); and (iii) severe, cloacal exstrophy (n = 31). These subgroups then were compared with identify factors that contribute to phenotype severity. RESULTS: Males were overrepresented in all subgroups. A relatively high prevalence of cleft lip, with or without cleft palate, was observed. Maternal smoking and medical radiation during the first trimester were associated with the severe cloacal exstrophy phenotype. Compliance with periconceptional folic acid supplementation was associated with the mildest phenotype (epispadias). CONCLUSIONS: Periconceptional folic acid supplementation appears to prevent the development of the severe phenotype of BEEC.
Subject(s)
Bladder Exstrophy/epidemiology , Epispadias/epidemiology , Adult , Antacids/therapeutic use , Cleft Lip/epidemiology , Cleft Palate/epidemiology , Europe/epidemiology , Female , Fertilization in Vitro/statistics & numerical data , Folic Acid/therapeutic use , Humans , Male , Maternal Age , Middle Aged , North America/epidemiology , Paternal Age , Phenotype , Pregnancy , Pregnancy Trimester, First , Prenatal Care , Radiography/statistics & numerical data , Risk Factors , Severity of Illness Index , Sex Distribution , Smoking/epidemiology , Sperm Injections, Intracytoplasmic/statistics & numerical data , Surveys and Questionnaires , Vitamin B Complex/therapeutic useABSTRACT
INTRODUCTION: Anorectal malformations (ARM) range from mild anal to severe anorectal anomalies. Approximately 50% are estimated to be non-syndromic with multiple familial cases reported that suggest underlying genetic factors. These, however, still await identification. MATERIALS AND METHODS: We report a familial case of non-syndromic ARM with a mother and her two children being affected. Mother and daughter had mild ARM that had only been diagnosed after the index patient was born with a more severe form and ultrashort Hirschsprung's disease. To reveal the genetic cause in our family genome-wide array analysis was carried out to ascertain microaberrations characterized by loss or gain of genomic material. In addition, sequence analysis of four major Hirschsprung's disease genes (RET, EDNRB, EDN3, and GDNF) and the HLXB9 gene was performed to identify a mutation common to all three family members; however, these analyses did not reveal any causal genetic alteration. To demonstrate the frequency of familial non-syndromic cases, we performed a literature search revealing 59 families with at least two affected members. Sufficient description of ARM phenotype and affection status of relatives to surely classify them as familial non-syndromic forms was given for 22 families. CONCLUSION: The present family suggests that mild ARM may be overlooked in patients with non-specific clinical symptoms and that the incidence of ARM may thus be higher than previously estimated. With the new possibilities of whole exome sequencing, even small families hold the possibility to identify causal defects.