Oto-facio-osseous-gonadal syndrome: a new form of syndromic deafness?

In this study, we report on two brothers, born to consanguineous parents, with a syndrome of sensorineural deafness, short stature, cryptorchidism, inguinal hernia, brachycephaly, prominent forehead, flat face, downslanting palpebral fissures, low nasal root, hypoplastic alae and round tip to the nose, low-set prominent ears, narrow thorax, genu valgum, wormian bones, fusion of carpal bones, delayed bone age and congenital clubfeet. This combination of anomalies appears to be a previously undescribed syndrome, with probable autosomal recessive inheritance.     

X-linked myotubular myopathy: clinical and pathological findings in a family

A five-generation family with recessively inherited X-linked myotubular myopathy was investigated. Two of the affected boys, who were siblings and were verified by muscle biopsy to have the disease, died 3 days and 3 months, respectively, after birth. They showed marked hypotonus from birth, general muscle weakness and asphyxia. Three other boys, who were probably affected by the disease, had severe asphyxia and died shortly after birth. In three of the five cases there was polyhydramnios. The muscle biopsies of the two siblings revealed predominance of small fibres with central nuclei and accumulation of mitochondria in the central parts of the fibres. In one of the boys mainly the type 1 fibres were hypotrophic. The postmortem examination revealed variation in the involvement of different muscles, the anterior tibial muscle being the most severely affected. Intrafusal muscle fibres and myocardium were apparently unaffected. There was no involvement of the spinal cord. The clinical examination of two obligate carriers in the family revealed no muscle weakness but the muscle biopsy showed pathological changes including greatly increased variability of fibre size, and many fibres with central nuclei. The findings indicate that muscle biopsy is of value in genetic counselling to detect carriers although the observed changes were unspecific.     

Identification of an unbalanced X-autosome translocation by array CGH in a boy with a syndromic form of chondrodysplasia punctata brachytelephalangic type

Screening of a large series of patients with unexplained mental retardation with a 1 Mb BAC array resulted in the detection of several cryptic chromosomal imbalances. In this paper we present the findings of array CGH screening in a 14-year-old boy with the brachytelephalangic type of chondrodysplasia punctata, mental retardation and obesity. On several occasions, cytogenetic analysis of this boy revealed a normal karyotype. Subsequent screening with array CGH resulted in the detection of a distal 9p trisomy and distal Xp nullisomy caused by an unbalanced X;9 translocation: 46,Y,der(X)t(X;9)(p22.32;p23). The identification of this de novo chromosomal rearrangement not only made accurate genetic counselling possible but also explained most of the phenotypic abnormalities observed in this patient. This study confirms the power of array CGH in the detection of subtle or submicroscopic chromosomal changes.     

Terminal osseous dysplasia with pigmentary defects: clinical description of a new family

Terminal osseous dysplasia with pigmentary defects is an extremely rare condition characterized by the triad of pigmentary anomalies of the skin, skeletal abnormalities of the limbs and recurring digital fibromatosis of childhood, with considerable interfamilial and intrafamilial variability of expression. It has recently been added to the small group of X-linked dominant disorder with prenatal male lethality on the basis of a four-generation pedigree in which only females were affected, male progeny was decreased and the number of spontaneous abortions was increased. In this clinical report, we describe a 2-year-old girl with full expression of the syndrome including skin defects, skeletal anomalies and recurrent fibromatosis of fingers and toes and her mother who presents with only multiple hypertrophic oral frenula. As previously demonstrated, our patients also show an extremely skewed X-inactivation on blood cells, strongly suggesting that there is selective disadvantage for cells carrying the mutated gene on their active X chromosome. Terminal osseous dysplasia with pigmentary defects could represent an additional example of extreme intrafamilial variability as already described for other X-linked dominant disorders.     

Lipomatous myelomeningocele,athyrotic hypothyroidism,and sensorineural deafness: a new form of syndromal deafness?

This case report describes a 4 year old boy with the unique triad of lipomatous myelomeningocele, congenital hypothyroidism secondary to thyroid agenesis, and sensorineural deafness. While associations between deafness and abnormal thyroid function and deafness and sacral lipoma have previously been described, the constellation of findings in this patient has not been reported.     

Cardiovascular findings in congenital contractural arachnodactyly: Report of an affected kindred

Three generations of a kindred had a history and physical findings consistent with congenital contractural arachnodactyly (CCA) segregating in an autosomal-dominant manner. Six of the seven affected patients we examined had mitral valve prolapse (MVP) diagnosed clinically or by echocardiography. The family members without CCA did not have MVP. This association of cardiac involvement with CCA further lessens the distinction between CCA and the Marfan syndrome. The indication for ophthamologic and echocardiographic follow-up of patients carrying the diagnosis of CCA is stressed.     

X-Linked recessive primary retinal dysplasia: clinical findings in affected males and carrier females

Three unrelated families (two Jewish and one Druze) are reported, in which a total of eight males exhibited the ophthalmological findings of primary retinal dysplasia. Since our affected male members only have eye findings, this disorder is readily differentiated from Nome's disease in which other parts of the nervous system are involved. The family pedigrees along with the clinical features support an X-linked recessive mode of transmission for this condition. Female carriers for this gene may show varying types of retinal fold changes. In addition, most of these same presumed female carriers also demonstrated changes in the stroma of their irides, resulting in a gray to grayish-blue color. At present, it is not possible to state definitely whether or not this latter observation is a feature of the carrier state.     

Biallelic HERC1 mutations in a syndromic form of overgrowth and intellectual disability

We report two Colombian siblings affected by overgrowth, intellectual disability and facial dysmorphism. Exome (via NGS) and Sanger sequencing revealed that biallelic sequence variants in a novel gene (HERC1) might be related to the disease pathogenesis. These results provide useful data for future genotype–phenotype correlations and for a molecular diagnosis of overgrowth.     

Anticipation in a unique family with Charcot-Marie-Tooth syndrome and deafness: delineation of the clinical features and review of the literature

Charcot-Marie-Tooth disease (CMT) is a clinically and genetically heterogeneous group of polyneuropathies characterized by degeneration of peripheral nerves, resulting in distal muscle atrophy, sensory loss, and deformities of hands and feet. We have studied 34 individuals in a large 84-member four-generation central Illinois family with autosomal dominant Charcot-Marie-Tooth and deafness. Nerve conduction velocities are consistent with type 1 CMT. Audiological evaluation revealed both auditory neuropathy and cochlear involvement in affected individuals. There is increasing clinical severity and younger age of onset of CMT and deafness with each progressive generation, suggestive of anticipation (P < 0.05). The proband, a female diagnosed at birth with hypotonia, bilateral vocal cord palsy, swallowing incoordination, and hearing impairment, died at age 18 months. Another individual died at the age of 3 months from hypotonia later attributed to CMT. Genetic analysis indicated that affected individuals in this family do not have the common 1.4 Mb duplication associated with type 1A CMT; however, all affected individuals have a unique G to C transversion at position 248 in coding exon 3 of the peripheral myelin PMP22 gene located on chromosome 17p11.2-p12. This mutation is predicted to cause an Ala67Pro substitution in the second transmembrane domain of PMP22, consistent with the molecular cause of the CMT phenotype. However, it does not explain the cochlear component of the deafness, the clinical observation of anticipation, and other features in this family.     

Branchio-oto (BO) syndrome and oculoauriculo-vertebral phenotype: overlapping clinical findings in a child from a BO family

A three-generation BO family is presented: the proband showed, in addition to branchio-oto malformations, a severe condition with growth retardation, mandibular hypoplasia and vertebral anomalies resembling the oculo-auriculo-vertebral (OAV) phenotype. This family study supports the hypothesis of Rollnick and Kaye that the OAV spectrum may represent, in some cases, an extreme component of the BOR syndrome. The finding has relevant implications for genetic counselling regarding both conditions.     

Inheritance of skewed X chromosome inactivation in a large family with an X-linked recessive deafness syndrome

A new X-linked recessive deafness syndrome was recently reported and mapped to Xq22 (Mohr-Tranebjærg syndrome). In addition to deafness, the patients had visual impairment, dystonia, fractures, and mental deterioration. The female carriers did not have any significant manifestations of the syndrome. We examined X chromosome inactivation in 8 obligate and 12 possible carriers by using a polymerase chain reaction analysis of the methylation-dependent amplification of the polymorphic triplet repeat at the androgen receptor locus. Seven of 8 obligate carriers and 1 of 5 carriers by linkage analysis had an extremely skewed pattern in blood DNA not found in 30 normal females. The X inactivation pattern in fibroblast DNA from 2 of the carriers with the extremely skewed pattern was also skewed but to a lesser degree than in blood DNA. One obligate carrier had a random X inactivation pattern in both blood and fibroblast DNA. A selection mechanism for the skewed pattern is therefore not likely. The extremely skewed X inactivation in 8 females of 3 generations in this family may be caused by a single gene that influences skewing of X chromosome inactivation. © 1996 Wiley-Liss, Inc.     

Linkage analysis of 62 X-chromosomal loci excludes the X chromosome in an Icelandic family showing apparent X-linked recessive inheritance of neural tube defects

We report here the findings of a linkage analysis, involving numerous markers from the human X chromosome, in an attempt to localise a putative gene causing apparent X-linked spina bifida and anencephaly (SBA) in a large Icelandic pedigree. Two-point linkage analysis was performed using markers from 62 informative loci in this family. Although small positive lod scores were found at a number of these loci, none reached the significance level for linkage. Haplotypes were extensively analysed and found to exclude linkage to the X chromosome.     

Young people's experiences of growing up in a family affected by Huntington's disease

Previous research and clinical experience suggest that Huntington's disease (HD) can considerably affect family life, particularly for young people (YP) at risk. The goal of this study was to describe the experiences of YP from families affected by HD. YP were identified through the regional genetics clinic and the Scottish Huntington's Association. In-depth interviews were used to explore YP's experiences of finding out about HD in the family; perceptions of their own risk; caring activities; protective or risk factors; and the impact of HD on relationships with siblings, parents, extended family members, and the wider community. Thirty-three YP between the ages of 9 and 28 years were interviewed. A qualitative thematic analysis was undertaken. The analysis revealed four main themes: YP as carers, the worried well, those who cope, and those at risk/in need. These themes highlight the varied experience of growing up in a family affected by HD. Whilst some YP successfully coped, others experienced considerable problems and were at risk of physical and/or emotional harm. In understanding why some cope better than others, our findings suggest protective and risk factors within these themes. In particular, participants who grew up knowing about HD from an early age seemed to cope better.     

Arthrogryposis, perthes disease, and upward gaze palsy: a novel autosomal recessive syndromic form of arthrogryposis

In this article, the unusual combination of arthrogryposis, upward gaze palsy, and Perthes disease in two sisters and their cousin who are all part of an extended consanguineous Saudi family is reported. All patients had difficult to control bronchial asthma and subtle facial dysmorphism. Two of the three had pyloric stenosis, two were intellectually normal, and one had academic problems but had a history of birth hypoxia. Pedigree is consistent with an autosomal recessive mode of inheritance. Lack of previous reports suggests this represents a novel syndromic form of arthrogryposis.     

Nail-patella syndrome in an Indian family: clinical and linkage data

Of 11 persons found to have the nail-patella syndrome in an Indian family, two show malposition of teeth of a marked but unspecific nature. It will be difficult to determine whether this feature is one more effect of the nail-patella allele. The linkage estimate for the nail-patella and ABO loci (1 recombinant in 16 meiotic products) is consistent with estimates in families of European origin. The author is grateful to the members in the pedigree who so willingly offered themselves for the investigation. Thanks are also due to Mi D. Roy Choudhry, Deputy Keeper (Anthropology), National Museum, New Delhi, for his help during the study.