Search

Split-hand/foot malformation (SHFM) is a genetically heterogeneous congenital limb malformation typically limited to a defect of the central rays of the autopod, presenting as a median cleft of hands and feet. It can be associated with long bone deficiency or included in more complex syndromes. Among the numerous genetic causes, WNT10B homozygous variants have been recently identified in consanguineous families, but remain still rarely described (SHFM6; MIM225300). We report on three novel SHFM families harboring WNT10B variants and review the literature, allowing us to highlight some clinical findings. The feet are more severely affected than the hands and there is a frequent asymmetry without obvious side-bias. Syndactyly of third-fourth fingers was a frequent finding (62%). Polydactyly, which was classically described in SHFM6, was only present in 27% of patients. No genotype-phenotype correlation is delineated but heterozygous individuals might have mild features of SHFM, suggesting a dose-effect of the WNT10B loss-of-function., (© 2019 Wiley Periodicals, Inc.)

Waardenburg syndrome (WS) is characterized by an association of pigmentation abnormalities and sensorineural hearing loss. Four types, defined on clinical grounds, have been delineated, but this phenotypic classification correlates imperfectly with known molecular anomalies. SOX10 mutations have been found in patients with type II and type IV WS (i.e., with Hirschsprung disease), more complex syndromes, and partial forms of the disease. The phenotype induced by SOX10 mutations is highly variable and, except for the neurological forms of the disease, no genotype-phenotype correlation has been characterized to date. There is no mutation hotspot in SOX10 and most cases are sporadic, making it particularly difficult to correlate the phenotypic and genetic variability. This study reports on three independent families with SOX10 mutations predicted to result in the same missense mutation at the protein level (p.Met112Ile), offering a rare opportunity to improve our understanding of the mechanisms underlying phenotypic variability. The pigmentation defects of these patients are very similar, and the neurological symptoms showed a somewhat similar evolution over time, indicating a potential partial genotype-phenotype correlation. However, variability in gastrointestinal symptoms suggests that other genetic factors contribute to the expression of these phenotypes. No correlation between the rs2435357 polymorphism of RET and the expression of Hirschsprung disease was found. In addition, one of the patients has esophageal achalasia, which has rarely been described in WS., (© 2014 Wiley Periodicals, Inc.)

Congenital diaphragmatic hernia (CDH) has an incidence of around 1/3,000 births. The pathogenesis of this developmental anomaly remains largely unknown and the description of small chromosomal imbalances in cases of CDH is of major interest for the identification of candidate genes. We report on a tandem 4q31.23 triplication encompassing the EDNRA gene identified by array-CGH in a male presenting an isolated left postero-lateral CDH. This copy number variation was inherited from the asymptomatic father, carrier of a size-identical duplication. We demonstrate that EDNRA mRNA is over-expressed in the proband in blood tissue. Consistent with the expression of EDNRA in the developing diaphragm and the observation that the endothelin system is up-regulated in human and animal models of CDH, we conclude that the EDNRA triplication may be the cause of CDH in our patient., (© 2013 Wiley Periodicals, Inc.)

Microdeletion 15q24 is an emerging syndrome recently described, mainly due to increased use of array-CGH. Clinical features associate mild to moderate developmental delay, typical facial characteristics (high forehead and frontal hairline, broad eyebrows, downslanting palpebral features, long philtrum), hands (particularly proximal implanted thumbs) and genital anomalies (micropenis, hypospadias). We report here on four de novo cases having 2.5-6.1 Mb deletions involving 15q24: one 15q23q24.2 (Patient 1) and three 15q24.1q24.2 deletions (Patients 2-4). We correlate phenotype to genotype according to molecular boundaries of these deletions. Since bilateral iris coloboma and severe ano-rectal malformation were only present in Patient 1, we could link these anomalies to haploinsufficiency of 15q23 genes. Neither hypospadias nor micropenis were present in Patient 3 bearing the smallest deletion, therefore we could define 500 kb 15q24.1 region linked to these anomalies.

The p11.2-p12 region of human chromosome 17 is gene rich and composed of at least two genomically unstable domains: the Smith-Magenis syndrome region (17p11.2) and the Charcot-Marie-Tooth region (17p12), both of which are flanked by several low-copy repeat sequences. Homologous recombination between these flanking repeats results in either deletion- or duplication-associated phenotypes caused by a gene dosage effect. We report on the clinical phenotype of three patients presenting with either a 17p11.2 or 17p11.2p12 duplication, revealed by chromosome analysis and confirmed by fluorescent in situ hybridization analysis, high resolution genomic analysis of the 17p region using oligonucleotide array comparative genomic hybridization, and molecular studies with microsatellite markers. Two patients carry the 17p11.2 duplication, while the third one shows a larger duplication including the 17p12 region. The facial features observed in our patients include triangular face, full cheeks, smooth philtrum, thin upper lip, dental malocclusion, irregular eyebrows, and sparse hair, all of which are consistent with the pure proximal dup 17p phenotype. The patients' other clinical features are compared with previously published cases., (Copyright 2008 Wiley-Liss, Inc.)

The combination of pulmonary agenesis/dysgenesis/hypoplasia, microphthalmia/anophthalmia, and a diaphragmatic defect (agenesis or eventration) is a rare syndrome presumed to have an autosomal recessive mode of inheritance based on a report of affected siblings born to unaffected parents [Seller et al., 1996]. The condition is known as Spear syndrome and Matthew-Wood syndrome, although genetic heterogeneity cannot be ruled out. We report on eight patients with this condition including a living child, three sibs and three isolated cases. Most presented with fetal ultrasound findings of microphthalmia/anophthalmia, and diaphragmatic eventration/hernia and in five, cardiac abnormalities were also found. The earliest detection was at 20 weeks gestation. This is the second report of sibs affected with this condition, which supports an autosomal recessive mode of inheritance. We present the first and only reported living patient with this condition and expand the intrafamilial, interfamilial, and ethnic variability of this condition. We suggest changing the condition's name to PDAC to reflect the most important components of this condition.

This is a 3-year retrospective study of 107 cases presenting with limb anomalies detected either on prenatal ultrasound scan, or after birth. These limb malformations are developmental anomalies, and can be isolated, syndromic, or associated with multiple malformations. Cases were ascertained through the prenatal diagnosis center, the pediatrics department, and the feto-pathology department. Several criteria were analyzed including sex ratio, prenatal diagnosis, karyotype, termination of pregnancies, clinical or pathological examination, pediatric or surgical and/or genetic assessment, and whether or not a diagnosis was made. Positional deformities and syndactyly were excluded. Limb anomalies were detected prenatally in 45% of the cases, and a diagnosis was made in 78%, including isolated, syndromic, or chromosomal anomalies. Sixty-one per cent of the infants had follow-up, either pediatric, surgical, or genetic. Prenatal multidisciplinary assessment is fundamental to assist with counseling, as is the post-natal follow-up of the infant. The diagnosis, if made, will obviously influence the information that will be given to the parents and the management of the malformation. If the pregnancy is terminated, feto-pathological examination is essential to help make a diagnosis, and guide recurrence risks. We are currently undertaking a prospective study, and we will develop a protocol of investigations in the future, depending on the type of the malformation identified., (Copyright 2003 Wiley-Liss, Inc.)