Audiological phenotyping evaluation in KBG syndrome: Description of a multicenter review.

OBJECTIVES: Our objective was to reinforce clinical knowledge of hearing impairment in KBG syndrome. KBG syndrome is a rare genetic disorder due to monoallelic pathogenic variations of ANKRD11.The typical phenotype includes facial dysmorphism, costal and spinal malformation and developmental delay. Hearing loss in KBG patients has been reported for many years, but no study has evaluated audiological phenotyping from a clinical and an anatomical point of view. METHODS: This French multicenter study included 32 KBG patients with retrospective collection of data on audiological features, ear imaging and genetic investigations. RESULTS: We identified a typical audiological profil in KBG syndrome: conductive (71%), bilateral (81%), mild to moderate (84%) and stable (69%) hearing loss, with some audiological heterogeneity. Among patients with an abnormality on CT imaging (55%), ossicular chain impairment (67%), fixation of the stapes footplate (33%) and inner-ear malformations (33%) were the most common abnormalities. CONCLUSION: We recommend a complete audiological and radiological evaluation and an ENT-follow up in all patients presenting with KBG Syndrome. Imaging evaluation is necessary to determine the nature of lesions in the middle and inner ear.

Safety and efficacy of low-dose PI3K inhibitor taselisib in adult patients with CLOVES and Klippel-Trenaunay syndrome (KTS): the TOTEM trial, a phase 1/2 multicenter, open-label, single-arm study.

PURPOSE: PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients. METHODS: Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes. RESULTS: Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean -4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement). CONCLUSION: Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.

WDR72 Mutations Associated with Amelogenesis Imperfecta and Acidosis.

Dental enamel malformations, or amelogenesis imperfecta (AI), can be isolated or syndromic. To improve the prospects of making a successful diagnosis by genetic testing, it is important that the full range of genes and mutations that cause AI be determined. Defects in WDR72 (WD repeat-containing protein 72; OMIM *613214) cause AI, type IIA3 (OMIM #613211), which follows an autosomal recessive pattern of inheritance. The defective enamel is normal in thickness, severely hypomineralized, orange-brown stained, and susceptible to attrition. We identified 6 families with biallelic WDR72 mutations by whole exome sequence analyses that perfectly segregated with the enamel phenotype. The novel mutations included 3 stop-gains [NM_182758.2: c.377G>A/p.(Trp126*), c.1801C>T/p.(Arg601*), c.2350A>T/p.(Arg784*)], a missense mutation [c.1265G>T/p.(Gly422Val)], and a 62,138-base pair deletion (NG_017034.2: g.35441_97578del62138) that removed WDR72 coding exons 3 through 13. A previously reported WDR72 frameshift was also observed [c.1467_1468delAT/p.(Val491Aspfs*8)]. Three of the affected patients showed decreased serum pH, consistent with a diagnosis of renal tubular acidosis. Percentiles of stature and body weight varied among 8 affected individuals but did not show a consistent trend. These studies support that WDR72 mutations cause a syndromic form of AI and improve our ability to diagnose AI caused by WDR72 defects.

Dermatological manifestations in cardiofaciocutaneous syndrome: a prospective multicentric study of 45 mutation-positive patients.

BACKGROUND: Data on dermatological manifestations of cardiofaciocutaneous syndrome (CFCS) remain heterogeneous and almost without expert dermatological classification. OBJECTIVES: To describe the dermatological manifestations of CFCS; to compare them with the literature findings; to assess those discriminating CFCS from other RASopathies, including Noonan syndrome (NS) and Costello syndrome (CS); and to test for dermatological phenotype-genotype correlations. METHODS: We performed a 4-year, large, prospective, multicentric, collaborative dermatological and genetic study. RESULTS: Forty-five patients were enrolled. Hair abnormalities were ubiquitous, including scarcity or absence of eyebrows and wavy or curly hair in 73% and 69% of patients, respectively. Keratosis pilaris (KP), ulerythema ophryogenes (UO), palmoplantar hyperkeratosis (PPHK) and multiple melanocytic naevi (MMN; over 50 naevi) were noted in 82%, 44%, 27% and 29% of patients, respectively. Scarcity or absence of eyebrows, association of UO and PPHK, diffuse KP and MMN best differentiated CFCS from NS and CS. Oral acitretin may be highly beneficial for therapeutic management of PPHK, whereas treatment of UO by topical sirolimus 1% failed. No significant dermatological phenotype-genotype correlation was determined. CONCLUSIONS: A thorough knowledge of CFCS skin manifestations would help in making a positive diagnosis and differentiating CFCS from CS and NS.

Dermatological manifestations in Noonan syndrome: a prospective multicentric study of 129 patients positive for mutation.

BACKGROUND: Data on dermatological manifestations of Noonan syndrome (NS) remain heterogeneous and are based on limited dermatological expertise. OBJECTIVES: To describe the dermatological manifestations of NS, compare them with the literature findings, and test for dermatological phenotype-genotype correlations with or without the presence of PTPN11 mutations. METHODS: We performed a large 4-year, prospective, multicentric, collaborative dermatological and genetic study. RESULTS: Overall, 129 patients with NS were enrolled, including 65 patients with PTPN11-NS, 34 patients with PTPN11-NS with multiple lentigines (NSML), and 30 patients with NS who had a mutation other than PTPN11. Easy bruising was the most frequent dermatological finding in PTPN11-NS, present in 53·8% of patients. Multiple lentigines and café-au-lait macules (n ≥ 3) were present in 94% and 80% of cases of NSML linked to specific mutations of PTPN11, respectively. Atypical forms of NSML could be associated with NS with RAF1 or NRAS mutations. In univariate analysis, patients without a PTPN11 mutation showed (i) a significantly higher frequency of keratinization disorders (P = 0·001), including keratosis pilaris (P = 0·005), ulerythema ophryogenes (P = 0·0001) and palmar and/or plantar hyperkeratosis (P = 0·06, trend association), and (ii) a significantly higher frequency of scarce scalp hair (P = 0·035) and scarce or absent eyelashes (P = 0·06, trend association) than those with PTPN11 mutations. CONCLUSIONS: The cutaneous phenotype of NS with a PTPN11 mutation is generally mild and nonspecific, whereas the absence of a PTPN11 mutation is associated with a high frequency of keratinization disorders and hair abnormalities.

Molecular, clinical and neuropsychological study in 31 patients with Kabuki syndrome and KMT2D mutations.

Kabuki syndrome (KS-OMIM 147920) is a rare developmental disease characterized by the association of multiple congenital anomalies and intellectual disability. This study aimed to investigate intellectual performance in children with KS and link the performance to several clinical features and molecular data. We recruited 31 children with KMT2D mutations who were 6 to 16 years old. They all completed the Weschler Intelligence Scale for Children, fourth edition. We calculated all indexes: the Full Scale Intellectual Quotient (FSIQ), Verbal Comprehension Index (VCI), Perceptive Reasoning Index (PRI), Processing Speed Index (PSI), and Working Memory Index (WMI). In addition, molecular data and several clinical symptoms were studied. FSIQ and VCI scores were 10 points lower for patients with a truncating mutation than other types of mutations. In addition, scores for FSIQ, VCI and PRI were lower for children with visual impairment than normal vision. We also identified a discrepancy in indexes characterized by high WMI and VCI and low PRI and PSI. We emphasize the importance of early identification and intensive care of visual disorders in patients with KS and recommend individual assessment of intellectual profile.

Xq25 duplication: the crucial role of the STAG2 gene in this novel human cohesinopathy.

The Xq25 duplications syndrome has recently emerged as a distinct clinical entity. We report here on six new patients belonging to two unrelated families and harbouring an Xq25 microduplication detected by array CGH. Similarly to previously reported cases, the phenotype of our patients is characterized by delayed milestones, speech disturbance, intellectual disability, abnormal behaviours and a characteristic facial dysmorphism. The common duplicated interval allowed further refinement of the shortest region of overlap to 173 kb, including only one gene, STAG2, which encodes a component of the cohesin complex. We suggest that increased STAG2 gene copy number and dysregulation of its downstream target genes may be responsible for the specific clinical findings of this syndrome. Therefore, the Xq25 microduplication could be considered as a novel cohesinopathy, thus increasing the group of these disorders.

Molecular findings and clinical data in a cohort of 150 patients with anophthalmia/microphthalmia.

Anophthalmia and microphthalmia (AM) are the most severe malformations of the eye, corresponding respectively to reduced size or absent ocular globe. Wide genetic heterogeneity has been reported and different genes have been demonstrated to be causative of syndromic and non-syndromic forms of AM. We screened seven AM genes [GDF6 (growth differentiation factor 6), FOXE3 (forkhead box E3), OTX2 (orthodenticle protein homolog 2), PAX6 (paired box 6), RAX (retina and anterior neural fold homeobox), SOX2 (SRY sex determining region Y-box 2), and VSX2 (visual system homeobox 2 gene)] in a cohort of 150 patients with isolated or syndromic AM. The causative genetic defect was identified in 21% of the patients (32/150). Point mutations were identified by direct sequencing of these genes in 25 patients (13 in SOX2, 4 in RAX, 3 in OTX2, 2 in FOXE3, 1 in VSX2, 1 in PAX6, and 1 in GDF6). In addition eight gene deletions (five SOX2, two OTX2 and one RAX) were identified using a semi-quantitative multiplex polymerase chain reaction (PCR) [quantitative multiplex PCR amplification of short fluorescent fragments (QMPSF)]. The causative genetic defect was identified in 21% of the patients. This result contributes to our knowledge of the molecular basis of AM, and will facilitate accurate genetic counselling.

[Charcot-Marie-Tooth disease associated with periaxin mutations (CMT4F): Clinical, electrophysiological and genetic analysis of 24 patients]. / Maladie de Charcot-Marie-Tooth associée au gène de la périaxine (CMT4F) : description clinique, électrophysiologique et génétique de 24 patients.

Autosomal recessive Charcot-Marie-Tooth disease (AR-CMT) is often characterized by onset in early childhood and severe phenotype compared to the dominant forms. CMT disease associated with periaxin gene (PRX) is rare and characterized by demyelination limited to the major peripheral nerves. Following the discovery of a high frequency of a specific periaxin gene mutation (E1085fsX4 homozygote) in the Reunion Island, we examined all French patients known as carriers of the periaxin gene mutation. There were 24 patients. Eighteen were from the Reunion Island (6 families and 10 sporadic cases). The six remaining patients were in two families, each with two affected individuals, and two sporadic cases. The series included 17 female and seven male patients. Walking was acquired late, on average at 3.4±1.6 years. One patient never learned to walk. The Charcot Marie Tooth Neuropathy Score (CMTNS) averaged 24.5±8.1. Seven patients had been wheelchair-bound since the age of 24±22. Other symptoms were: scoliosis most often observed after the age of 12 years and sometimes complicated by a restrictive respiratory syndrome; foot deformity in 24 patients; strabismus; glaucoma; myopia. When conduction recordings are available, median nerve motor conduction was slow (<10m/s), associated with a major lengthening of distal latencies. Study of the periaxin gene should be considered in patients with severe demyelinating neuropathy associated with early infantile scoliosis. This disease leads to major disability (29% of patients in this series were wheelchair-bound) and to respiratory insufficiency. Genetic counselling is highly recommended for consanguineous families.

[Collodion baby and respiratory distress syndrome]. / Bébé collodion et syndrome de détresse respiratoire.

The congenital ichthyosis appears mainly in the form of collodion baby. This one can be suspected in case of polyhydramnios associated with a snowy aspect of the amniotic liquid in the antenatal echography. The reported four cases of collodion baby were premature children having presented a respiratory distress syndrome of variable gravity. The pulmonary disease was of multifactorial origin. The outcome was favorable for four children.

[PELVIS/SACRAL syndrome with livedoid haemangioma and amniotic band]. / PELVIS/SACRAL syndrome avec hémangiome livédoïde et bride amniotique.

BACKGROUND: PELVIS or SACRAL syndrome denotes the association of local haemangioma and malformation in the pelvic region. In this paper, we report a case noteworthy on account of the initially livedoid appearance of the haemangioma as well as associated amniotic banding of an upper limb. PATIENTS AND METHODS: A newborn male infant underwent left colostomy on the day of birth due to anal imperforation and anomalies of the external genital organs with sexual ambiguity. Examination of the skin and appendages revealed poorly delineated hypopigmentation in the sacrolumbar region and a fibrous groove around the right arm characteristic of amniotic band syndrome. Sacrolumbar and pelvic MRI scans revealed deviation towards the left of the last three sacral vertebrae with no medullary anomalies. Retrograde cystography showed a recto-uretral fistula. Progression of the infant's condition was marked by the appearance during the first month of a flat, violaceous, angiomatous, livedoid lesion in the middle of the buttocks and the perineum and a linear lesion on the rear aspect of the right lower limb. The skin biopsy of this lesion revealed a single capillary lobule at the dermal-hypodermal junction of non-specific appearance but with marked Glut1 expression by endothelial cells highly evocative of infantile haemangioma. DISCUSSION: Segmented haemangiomas are commonly associated with extracutaneous abnormalities. By analogy with PHACE syndrome, defined as association of segmented facial haemangioma with cerebral, ocular and cardio-aortic abnormalities, PELVIS/SACRAL syndrome denotes the association of segmented haemangioma of the loins (sacrolumbar region, buttocks or perineum=napkin haemangioma) with spinal dysraphia affecting the sacrolumbar spine, the terminal medullary cone, the genitourinary organs and the anal region to different degrees. Diagnosis of haemangioma associated with PELVIS/SACRAL syndrome may be delayed or complicated due to the macular, telangiectasic or livedoid appearance commonly seen. To our knowledge, there have been no reports to date of an association of amniotic banding with haemangioma or perineal dysraphia.

Array-based comparative genomic hybridisation identifies high frequency of cryptic chromosomal rearrangements in patients with syndromic autism spectrum disorders.

BACKGROUND: Autism spectrum disorders (ASD) refer to a broader group of neurobiological conditions, pervasive developmental disorders. They are characterised by a symptomatic triad associated with qualitative changes in social interactions, defect in communication abilities, and repetitive and stereotyped interests and activities. ASD is prevalent in 1 to 3 per 1000 people. Despite several arguments for a strong genetic contribution, the molecular basis of a most cases remains unexplained. About 5% of patients with autism have a chromosome abnormality visible with cytogenetic methods. The most frequent are 15q11-q13 duplication, 2q37 and 22q13.3 deletions. Many other chromosomal imbalances have been described. However, most of them remain undetectable using routine karyotype analysis, thus impeding diagnosis and genetic counselling. METHODS AND RESULTS: 29 patients presenting with syndromic ASD were investigated using a DNA microarray constructed from large insert clones spaced at approximately 1 Mb intervals across the genome. Eight clinically relevant rearrangements were identified in 8 (27.5%) patients: six deletions and two duplications. Altered segments ranged in size from 1.4 to 16 Mb (2-19 clones). No recurrent abnormality was identified. CONCLUSION: These results clearly show that array comparative genomic hybridisation should be considered to be an essential aspect of the genetic analysis of patients with syndromic ASD. Moreover, besides their importance for diagnosis and genetic counselling, they may allow the delineation of new contiguous gene syndromes associated with ASD. Finally, the detailed molecular analysis of the rearranged regions may pave the way for the identification of new ASD genes.

Gorlin syndrome presenting as prenatal chylothorax in a girl.

Gorlin syndrome (GS), also known as nevoid basal cell carcinoma syndrome, is a rare autosomal dominant condition with an estimated prevalence of 1:57 000. GS is associated with congenital malformations and predisposition to neoplasms. The main features observed in patients with GS are basal cell carcinomas, odontogenic keratocysts, skeletal anomalies including scoliosis and bifid ribs, palmar and plantar epidermal cysts, facial dysmorphism, and cerebral falx calcification. More than 100 other clinical manifestations have also been described in the literature including ovarian fibroma, enlarged cerebral ventricles, and lymphatic as well as chylous mesenteric cysts. The Patched (PTCH) gene is responsible for GS when mutated. Here, we report on a prenatal diagnosis of GS in a girl with a chylothorax, a previously unreported feature in GS. We discuss the clinical features observed in this family and we comment on the molecular studies that allowed us to describe a previously unreported Patched gene mutation.

A new case of a severe clinical phenotype of the cat-eye syndrome.

A new case of severe clinical phenotype of the cat-eye syndrome: We report on a female infant with severe clinical phenotype of Cat-Eye Syndrome (CES). At birth, she had respiratory distress and marked hypotonia. Physical examination showed major craniofacial anomalies including microcephaly, bilateral total absence of the external ears, hypertelorism, bilateral ocular coloboma of iris and micrognathia. In addition, she had anal stenosis, a patent ductus arteriosus and intra- and extra- hepatic biliary atresia. She deteriorated with the development of bradycardia. She died at age one month of cardiac failure. Cytogenetic analysis of the proband showed an extra de novo small bisatelllited marker chromosome in all cells examined. Molecular cytogenetic analysis with fluorescence in situ hybridization (FISH) identified the marker as a CES chromosome. Thus, the patient's karyotype was: 47, XX, +idic(22)(pter-->q11.2 ::q11.2-->pter). The duplication breakpoints giving rise to the CES chromosome were distal to the DiGeorge Syndrome (DGS) locus 22q11.2. The marker could be classed as a type 11 symmetrical (10). According to a recent review of CES literature (1) only 41 % of the CES patients have the combination of iris coloboma, anal anomalies and preauricular anomalies. Almost 60% are hard to recognize by their phenotype alone. Only twelve patients showed a severe clinical phenotype leading to the death of the child. This phenotypic variability increases the difficulties of genetic counseling.