25 research outputs found

    Loss of the BMP Antagonist, SMOC-1, Causes Ophthalmo-Acromelic (Waardenburg Anophthalmia) Syndrome in Humans and Mice

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    Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2 identified homozygous mutations in SMOC1 (SPARC-related modular calcium binding 1) in eight unrelated families. Four of these mutations are nonsense, two frame-shift, and two missense. The missense mutations are both in the second Thyroglobulin Type-1 (Tg1) domain of the protein. The orthologous gene in the mouse, Smoc1, shows site- and stage-specific expression during eye, limb, craniofacial, and somite development. We also report a targeted pre-conditional gene-trap mutation of Smoc1 (Smoc1tm1a) that reduces mRNA to ∼10% of wild-type levels. This gene-trap results in highly penetrant hindlimb post-axial oligosyndactyly in homozygous mutant animals (Smoc1tm1a/tm1a). Eye malformations, most commonly coloboma, and cleft palate occur in a significant proportion of Smoc1tm1a/tm1a embryos and pups. Thus partial loss of Smoc-1 results in a convincing phenocopy of the human disease. SMOC-1 is one of the two mammalian paralogs of Drosophila Pentagone, an inhibitor of decapentaplegic. The orthologous gene in Xenopus laevis, Smoc-1, also functions as a Bone Morphogenic Protein (BMP) antagonist in early embryogenesis. Loss of BMP antagonism during mammalian development provides a plausible explanation for both the limb and eye phenotype in humans and mice

    Can environmental or occupational hazards alter the sex ratio at birth? A systematic review

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    More than 100 studies have examined whether environmental or occupational exposures of parents affect the sex ratio of their offspring at birth. For this review, we searched Medline and Web of Science using the terms ‘sex ratio at birth’ and ‘sex ratio and exposure’ for all dates, and reviewed bibliographies of relevant studies to find additional articles. This review focuses on exposures that have been the subject of at least four studies including polychlorinated biphenyls (PCBs), dioxins, pesticides, lead and other metals, radiation, boron, and g-forces. For paternal exposures, only dioxins and PCBs were consistently associated with sex ratios higher or lower than the expected 1.06. Dioxins were associated with a decreased proportion of male births, whereas PCBs were associated with an increased proportion of male births. There was limited evidence for a decrease in the proportion of male births after paternal exposure to DBCP, lead, methylmercury, non-ionizing radiation, ionizing radiation treatment for childhood cancer, boron, or g-forces. Few studies have found higher or lower sex ratios associated with maternal exposures. Studies in humans and animals have found a reduction in the number of male births associated with lower male fertility, but the mechanism by which environmental hazards might change the sex ratio has not yet been established

    A large Turkish kindred with syndactyly type II (synpolydactyly). 1. Field investigation, clinical and pedigree data.

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    A very large Turkish family with syndactyly type II (synpolydactyly (SPD)) is described, which originated from and is mainly concentrated in the village of Derbent, Afyon. The kindred consists of 425 subjects over seven generations, of whom 182 are affected. It appears that a founder effect in this village has led to this extensive kindred. This condition is inherited as an autosomal dominant trait with variable expressivity and an estimated penetrance of 96%. Penetrance is different between the upper (96%) and lower (69.5%) extremities. No excess of affected males or females or other associated features were documented in this condition. Variations in the involvement of one or both hands, upper or lower extremities, bone and soft tissue, as well as variation in the affected subjects of two successive generations were documented. We also noted that metacarpal and metatarsal involvement and middle phalangeal hypoplasia of the feet are the consistent features of SPD and, therefore, should be considered as characteristic of this phenotype. We observed four different phenotypes in various branches of the Derbent kindred: (1) subjects presenting typical features of SPD; (2) subjects exhibiting both pre- and post-axial polydactyly simultaneously; (3) persons manifesting postaxial polydactyly type A; and (4) subjects born to two affected parents with severe hand and foot deformities that have not been previously described in any other SPD families (that is, homozygotes). A total of 27 affected offspring were born to two such affected parents, of whom seven are expected to be homozygous for the SPD gene. This group is presented in an accompanying paper in this issue of the Journal. A molecular study is currently under way to identify the chromosomal location of the defective gene

    Pleural calcification, pleural mesotheliomas, and bronchial cancers caused by tremolite dust.

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    Around the town of Cermik in south-east Turkey there are many deposits of asbestiform minerals, some of which are used to make whitewash or stucco. A sample of 7000 of the population revealed 461 (6.5%) with pleural thickening and calcification, of whom 103 (1.47% of the total) had evidence of interstitial pulmonary fibrosis. Forty-one patients with respiratory cancer were admitted to the Diyarbakir Chest Hospital from around Cermik and from a comparable area of equal population (but without asbestos deposits) in 1977-8. Of these 23 were mesotheliomas, 22 coming from around Cermik. In addition, 11 of the 18 primary bronchial cancers came from around Cermik. A similar excess of mesothelioma and bronchial cancer had been admitted from the Cermik area in previous years. The whitewash or stucco material has been shown to contain fibrous tremolite and non-fibrous antigorite/lizardite, chlorite, and talc. A lung biopsy of a patient from Cermik contained large numbers of tremolite fibres, both free and forming asbestos bodies. There were only occasional chrysotile fibres

    A large Turkish kindred with syndactyly type II (synpolydactyly). 2. Homozygous phenotype?

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    Syndactyly type II (synpolydactyly (SPD)) is an autosomal dominant condition with typical abnormalities of the distal parts of both upper and lower limbs. We report here a previously undescribed phenotypic feature of people with severe hand and foot deformities who were born to two affected parents. This is the first example of SPD subjects manifesting a very distinctive phenotype, suggesting that they must be homozygous for this condition. The typical characteristic clinical features in these subjects are as follows: (1) short hands with wrinkled fatty skin and short feet; (2) complete soft tissue syndactyly involving all four limbs; (3) polydactyly of the preaxial, mesoaxial, and postaxial digits of the hands; (4) loss of the normal tubular shape of the carpal, metacarpal, and phalangeal bones, so as to give polygonal structures; (5) loss of the typical structure of the cuboid and all three cuneiform bones while the talus calcaneus and navicular bones remain intact; (6) large bony islands instead of metatarsals, most probably because of cuboid-metatarsal and cuneiform-metatarsal fusions; and (7) severe middle phalangeal hypoplasia/aplasia as well as fusion of some phalangeal structures that are associated with the loss of normal phalangeal pattern. We report seven subjects with this phenotype from three different branches of a very large SPD pedigree exhibiting the same phenotype with minimal variation. In mice, the Polysyndactyly (Ps) mutation shows a pattern of synpolydactyly very similar to that of human SPD, suggesting that they may well be homologous mutations. A molecular genetic study is currently under way to determine the chromosomal location of the SPD locus in humans and to identify the corresponding homologous region in mice

    LGBT+ Networks, 2017-2020

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    The LGBT+ Networks data consists of 9 case studies of LGBT+ employee networks in the NHS (located in England, Scotland and Wales) and 118 short video clips from LGBT+ people and their allies. Qualitative data form the case studies was collected from September 2017 to October 2019. Each case study comprises transcripts from network meetings (38) and transcripts from interviews (65) with network chairs, network members, allies, EDI/HR representatives and chief executive officers in organisations. The short video clips (118) were recorded in a custom-made video booth located in 8 different organisations during LGBT+ history month in February 2020.This research aims to offer better understanding of how lesbian, gay, bisexual and transgender (LGBT+) employee networks are run and what they can do to improve relationships between colleagues, and ultimately, improve the wellbeing of LGBT+ employees. In doing so, the research focuses on LGBT+ employee networks within the NHS in nine different institutions by administering surveys, interviewing network members and taking part in network activities. To achieve our research aims, the following objectives have been set: 1) Establish baseline understanding of how LGBT+ employee networks operate; 2) Map network membership and explore ways of addressing insufficient representation of different groups with the networks; 3) Explore what support is in place to archive networks' vision and what barriers exists to realise this vision; 4) Examine ways of using LGBT+ employee networks to address negativity towards gender and sexual minorities more effectively.</p
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