INTU-related oral-facial-digital syndrome type VI: A confirmatory report.

Oral-facial-digital (OFD) syndromes are a subgroup of ciliopathies distinguished by the co-occurrence of hamartomas and/or multiple frenula of the oral region and digital anomalies. Several clinical forms of OFD syndromes are distinguished by their associated anomalies and/or inheritance patterns, and at least 20 genetic types of OFD syndromes have been delineated. We describe here a child with preaxial and postaxial polydactyly, lingual hamartoma, a congenital heart defect, delayed development and cerebellar peduncles displaying the molar tooth sign. Whole-exome sequencing and SNP array identified compound heterozygous variants in the INTU gene, which encodes a protein involved in the positioning of the ciliary basal body. INTU is a subunit of the CPLANE multiprotein complex essential for the assembly of IFT-A particles and intraflagellar transport. This report of a second patient with INTU-related OFD syndrome and the further delineation of its neuroimaging and skeletal phenotype now allow INTU-related OFD syndromes to be classified within the OFD syndrome type VI group. Patients display a phenotype similar to that of mice with a hypomorphic mutation of Intu, but with the addition of a heart defect.

Mutations in 3 genes (MKS3, CC2D2A and RPGRIP1L) cause COACH syndrome (Joubert syndrome with congenital hepatic fibrosis).

OBJECTIVE: To identify genetic causes of COACH syndrome BACKGROUND: COACH syndrome is a rare autosomal recessive disorder characterised by Cerebellar vermis hypoplasia, Oligophrenia (developmental delay/mental retardation), Ataxia, Coloboma, and Hepatic fibrosis. The vermis hypoplasia falls in a spectrum of mid-hindbrain malformation called the molar tooth sign (MTS), making COACH a Joubert syndrome related disorder (JSRD). METHODS: In a cohort of 251 families with JSRD, 26 subjects in 23 families met criteria for COACH syndrome, defined as JSRD plus clinically apparent liver disease. Diagnostic criteria for JSRD were clinical findings (intellectual impairment, hypotonia, ataxia) plus supportive brain imaging findings (MTS or cerebellar vermis hypoplasia). MKS3/TMEM67 was sequenced in all subjects for whom DNA was available. In COACH subjects without MKS3 mutations, CC2D2A, RPGRIP1L and CEP290 were also sequenced. RESULTS: 19/23 families (83%) with COACH syndrome carried MKS3 mutations, compared to 2/209 (1%) with JSRD but no liver disease. Two other families with COACH carried CC2D2A mutations, one family carried RPGRIP1L mutations, and one lacked mutations in MKS3, CC2D2A, RPGRIP1L and CEP290. Liver biopsies from three subjects, each with mutations in one of the three genes, revealed changes within the congenital hepatic fibrosis/ductal plate malformation spectrum. In JSRD with and without liver disease, MKS3 mutations account for 21/232 families (9%). CONCLUSIONS: Mutations in MKS3 are responsible for the majority of COACH syndrome, with minor contributions from CC2D2A and RPGRIP1L; therefore, MKS3 should be the first gene tested in patients with JSRD plus liver disease and/or coloboma, followed by CC2D2A and RPGRIP1L.

Novel and recurrent mutations in the genes encoding keratins K6a, K16 and K17 in 13 cases of pachyonychia congenita.

Thirteen patients with pachyonychia congenita types 1 and 2 were studied, two of which had a family history of pachyonychia and 11 of which were sporadic cases. Heterozygous mis-sense or small in-frame insertion/deletion mutations were detected in the genes encoding keratins K6a, K16, and K17 in all cases. Three novel mutations, F174V, E472K, and L469R were found in the K6a gene. Two novel mutations, M121T and L128Q were detected in K16. Similarly, three novel mutations, L95P, S97del, and L99P were found in K17. In addition, we identified recurrent mutations N171del (three instances) and F174S in K6a and R94H in K17. Analysis of both phenotype and genotype data led to the following conclusions: (i) K6a or K16 mutations produce the pachyonychia congenita type 1 phenotype, whereas K17 (or K6b) mutations cause pachyonychia congenita type 2; (ii) the presence of pilosebaceous cysts following puberty is the best indicator of pachyonychia congenita type 2; (iii) prepubescent patients are more difficult to classify due to the lack of cysts; and (iv) natal teeth are indicative of pachyonychia congenita type 2, although their absence does not preclude the pachyonychia congenita type 2 phenotype. This study establishes useful diagnostic criteria for pachyonychia congenita types 1 and 2, which will help limit unnecessary DNA analysis in the diagnosis and management of this genetically heterogeneous group of genodermatoses.

New oral-acral syndrome with partial agenesis of the maxillary bones.

We report on a woman with congenital defect of the anterior part of the maxillary bone (including absence of incisors and canines) without cleft lip or palate, and ectrodactyly of the feet. This syndrome appears to represent a new entity of unknown cause.

Lambotte syndrome: microcephaly, holoprosencephaly, intrauterine growth retardation, facial anomalies, and early lethality--a new sublethal multiple congenital anomaly/mental retardation syndrome in four sibs.

We report on an Arabic sibship originating from Morocco in which four children manifest an undiagnosed sublethal multiple congenital anomaly/mental retardation (MCA/MR) syndrome of intrauterine growth retardation (IUGR), microcephaly, large soft pinnae, telecanthus or true hypertelorism with squint, flat face, unusual hooked nose, very narrow mouth, retrognathia, and extremely severe neurologic impairment. One child was stillborn. Three others died in a cachectic state during their second year. One child had a severe cerebral malformation compatible with semilobar holoprosencephaly. Other inconstant manifestations are anterior chamber cleavage defect, preaxial polydactyly of feet, interventricular septal defect, and atresia of the external auditory meatus. Autosomal recessive inheritance is likely.

Koraxitrachitic syndrome: a syndromic form of self-healing collodion baby with residual dappled atrophy of the derma.

We report on a child with a generalized skin disorder associated with other minor anomalies. At birth, the child presented as a collodion baby, with patchy erythema, generalized irregular dermal atrophy, alopecia, absent eyelashes and eyebrows, and conjunctival pannus. He also had hypertelorism, prominent nasal root, large mouth, micrognathia, brachydactyly, syndactyly involving all interdigital spaces, and camptodactyly of fingers III-V. The hyperkeratotic membrane thinned progressively, leaving a mottled reticulated skin atrophy, with patchy areas of yellowish hyperpigmentation and papyraceous areas. Hair and nails were dystrophic. Mental development was borderline normal. The histological hallmarks of the skin manifestations combined orthokeratotic hyperkeratosis and marked atrophy of the dermis. The dermal extracellular matrix was immature, and factor XIII-a positive dendrocytes were rare and globular rather than dendritic. We frame as a hypothesis that the disease is due to or associated with a defect in maturation of a subset of dermal dendrocytes during fetal life. This entity may be designed as the koraxitrachitic syndrome (kappaomicronrhoalphaxi:grapnel- taurhoalphachiiotatauepsilonsigma: roughness)

Phenotypic variability in van der Woude syndrome.

The association of lower lip pits with cleft lip and/or palate defines the van der Woude syndrome (VWS). VWS has an autosomal dominant mode of inheritance wiht a high penetrance and a variable expression. A gene involved in the origin of VWS is linked to loci on chromosome 1q32-q41. The gene might be involved in the programmed cell death of neural crest derived cells. Other malformations have been associated with the syndrome (dental defects, syngnathia, limb abnormalities, popliteal webs...). We report 4 cases with VWS demonstrating the wide clinical variability. One case shows brain abnormalities that might be part of the clinical spectrum of VWS.

Microcephaly, macrotia, unusual mimics and mental retardation syndrome: new syndrome or variant of De Lange type 2 syndrome.

We report a boy who shows a severe microcephaly, with mild mental retardation and hypotonia, and a dysmorphic facies: (flat profile, arched eyebrows, mild ptosis, short nose with raised basis, large tip and anteverted nares, long, smooth philtrum, narrow mouth with down turned corners, very large, backward tilted ears, with a prominent lobule, retrognathism and very small and widely spaced, although normally shaped teeth. Vesicoureteral reflux was present. The mother showed similar aspect, large ears, and a grinning smile. This appear to represent an undescribed phenotype which share some resemblance to mild Cornelia de Lange and Kabuki syndromes.

A new form of mandibulofacial dysostosis with macroblepharon and macrostomia.

We report on a girl aged 7 years with normal mental development but an unusual form of mandibulofacial dysostosis. The hallmarks of the syndrome are a round, flat face, severe hypertelorism, downslanting palpebral fissures extending to the temples, a broad nasal base, anteverted nares, small, posteriorly rotated ears, a long, smooth philtrum, a thin upper lip, striking macrostomia, retrognathism with reduced height of the mandible, and irregularly placed teeth, some to them missing.

New syndrome: clavicle hypoplasia, facial dysmorphism, severe myopia, single central incisor and peripheral neuropathy.

A new syndrome of unknown origin is reported, consisting of facial dysmorphism (upward slanted palpebral fissures, single superior central incisor, narrow, cylindrical nose with hypoplastic alae), bilateral agenesis of the clavicles, limited movements of elbow and fingers, calf atrophy and pes cavus with abolished reflexes (Charcot-Marie-Tooth syndrome, unspecified type).

Diabetes mellitus, mental retardation, lipodystrophy and dysmorphic traits.

We report on a mentally retarded girl with dysmorphic facies (hypertelorism, upslanting palpebral fissures, blepharophimosis, prominent teeth), who suffered from juvenile-onset insulinopenic diabetes mellitus and lipodystrophy. She could represent an undescribed MCA/MR syndrome.

Bony syngnathia, vertebral segmentation defect, coloboma, microcephaly and mental retardation: confirmation of Dobrow syndrome and review of syndromal syngnathias.

Congenital bony fusion of the maxilla and mandible is a rare condition. Two classifications were previously proposed dealing exclusively with craniofacial malformations. Most of the reported cases to date represent either aglossia-adactylia or hemifacial microsomia syndromes. We report a young girl with bony syngnathia associated with multiple defects (severe microcephaly, coloboma, vertebral segmentation defects), growth and mental delay. This patient is very similar to the patient described by Dobrow in 1983 and confirms the existence of this extremely rare disorder.

A new form of skeletal dysplasia with amelogenesis imperfecta and platyspondyly.

We report two patients, born of consanguineous parents, affected by a disorder resulting in mild growth retardation. Hallmarks are amelogenesis imperfecta (absence of the enamel cap) associated with brachyolmia-like anomalies: platyspondyly with short pedicles, narrow intervertebral and interpedicular distances, rectangular-shaped vertebrae with posterior scalloping and herniation of the nuclei, and broad femoral necks. Inheritance appears to be autosomal recessive.

Mental retardation with blepharo-naso-facial abnormalities and hand malformations: a new syndrome?

A syndrome involving facial abnormalities (telecanthus, epicanthus, broad flattened nose, large inverted W-shaped mouth and malformed ears), malformed extremities (camptodactyly, clinodactyly, interdigital webbing and joint hyperlaxity) and mental retardation is described in a girl at birth and at 11 years old. A comparison with Pashayan-Pruzansky syndrome, fetal alcohol syndrome, VATER association, Marden-Walker syndrome and Tel-Hashomer syndrome is discussed. We suggest this patient represents a new malformation syndrome or an extreme phenotypic variant of one of the above-mentioned syndromes.

Brachymorphism-onychodysplasia-dysphalangism syndrome.

Three unrelated children are reported with intrauterine proportionate growth retardation and facial dysmorphism (broad nose, flat malar area, large mouth, pointed chin), microcephaly, hypo/aplasia of the terminal fifth digits, and (sub)normal intelligence. Radiological findings include hypo/aplasia or fusion of the distal phalanges of the fifth finger and toe, brachymesophalangism V, and nail dysplasia or aplasia. One child had cystic adenomatoid disease of the lung. The pattern of anomalies presented by these children closely resembles a syndrome incompletely delineated in 1971 by Senior in six children, which has often been considered to be a mild form of Coffin-Siris syndrome. We suggest that this is an independent entity (BOD syndrome). The aetiology is still unknown. Differential diagnosis and nosological difficulties are discussed.

Localization of a gene for oculodentodigital syndrome to human chromosome 6q22-q24.

Oculodentodigital syndrome (ODD) is a congenital, autosomal dominant disorder which affects the development of the face, eyes, limbs and dentition. Spastic paraparesis is thought to be an occasional manifestation of the disorder. Type III syndactyly, which occurs as part of ODD, has also been reported to occur as an isolated entity. In the current investigation, a total genome search for the location of the ODD locus was instigated and linkage to polymorphic markers located on chromosome 6q established (pairwise Zmax = 9.37; theta = 0.001). Analysis of a large family with type III syndactyly, but atypical facial features, further suggested that isolated type III syndactyly is also located in this same region of the genome.

Bruck syndrome: neonatal presentation and natural course in three patients.

Three unrelated patients with congenital arthrogryposis and brittle bones, the main neonatal signs of Bruck syndrome, are presented. In infancy and early childhood recurrent fractures of ribs and long bones and persistent Wormian bones in the calvarium are reminiscent of osteogenesis imperfecta (OI) even with white sclerae, normal dental quality and normal hearing as important clinical negatives. The diagnosis was made before two years of age in two, and in adolescence in the third patient. The latter's radiologically documented long-term natural course reveals slow progressivity of osteopenia and growth deficiency, worsening tendon contractures and pterygia in addition to increasing spine and pelvis deformation. Mental development remains normal. Bruck syndrome is monogenic and probably due to homozygosity of an as yet unidentified gene. As no alteration in the collagens I and III is detected and molecular screening reveals no mutation in the COL1A1 and COL1A2 genes, the pathogenesis of this severe disorder of connective tissue remains largely unknown.