RESUMO
Multiple cDNAs belonging to the c-erbA gene family encode proteins that bind T3 with high affinity. However, the biological functions of these multiple thyroid hormone receptors have not yet been clarified. Generalized thyroid hormone resistance (GTHR) refers to a human syndrome characterized by tissue refractoriness to the action of thyroid hormones; several studies have suggested quantitative or qualitative defects in T3 binding to nuclear receptors in certain kindreds. To investigate the biological functions of the c-erbA genes, c-erbA alpha and c-erbA beta, we tested the hypothesis that an abnormal c-erbA gene product is present in GTHR by examining these genes in members of one kindred. Restriction enzyme analysis failed to identify an abnormal pattern in affected individuals suggesting no rearrangements or large deletions. However, we demonstrated that the gene conferring the GTHR phenotype is tightly linked to the c-erbA beta locus on chromosome 3. This linkage strongly suggests that the c-erbA beta gene is important in man as a thyroid hormone receptor and identifies a putative c-erbA beta mutant phenotype with central nervous system, pituitary, liver, metabolic, and growth abnormalities.
Assuntos
Ligação Genética , Proteínas Proto-Oncogênicas/genética , Doenças da Glândula Tireoide/genética , Tri-Iodotironina/metabolismo , Resistência a Medicamentos , Humanos , Linhagem , Polimorfismo de Fragmento de Restrição , Receptores dos Hormônios Tireóideos , Síndrome/genética , Doenças da Glândula Tireoide/metabolismoRESUMO
A familial occurrence of Netherton's syndrome with typical features in two sisters is documented. Detailed illustrations of the associated hair shaft abnormalities and results of extensive immunologic investigations are presented.
Assuntos
Cabelo/patologia , Dermatopatias/genética , Pré-Escolar , Feminino , Humanos , Masculino , Dermatoses do Couro Cabeludo/patologia , Dermatopatias/sangue , Dermatopatias/imunologia , Dermatopatias/patologia , Síndrome/genéticaAssuntos
Tronco Encefálico/enzimologia , Encefalomalacia/urina , Tronco Encefálico/metabolismo , Encefalomalacia/enzimologia , Encefalomalacia/genética , Encefalomalacia/metabolismo , Heterozigoto , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Deficiência Intelectual/urina , Fosfotransferases/metabolismo , Transtornos Psicomotores/genética , Transtornos Psicomotores/metabolismo , Transtornos Psicomotores/urina , Síndrome/genética , Síndrome/metabolismo , Síndrome/urina , Tiamina Pirofosfato/metabolismoAssuntos
Diabetes Mellitus Tipo 1/genética , Atrofia Óptica/genética , Adulto , Audiometria , Feminino , Genes Recessivos , Humanos , Masculino , Linhagem , Síndrome/genética , Acuidade VisualRESUMO
Four sibs of non-consanguineous parents who had myotonia from late infancy are described. Mild to moderate mental retardation, severe bone abnormalities of the vertebral column (mainly in the thoracolumbar region), and short stature were also observed. Autosomal recessive inheritance is demonstrated. These cases are compared with reported cases of the Schwartz-Jampel syndrome.
Assuntos
Deficiência Intelectual/genética , Miotonia/genética , Esqueleto/anormalidades , Adolescente , Adulto , Feminino , Genes Recessivos , Humanos , Masculino , Linhagem , Síndrome/genética , Tórax/anormalidadesRESUMO
Genetically different bone dysplasias may manifest themselves in similar patterns of skeletal abnormalities. It is proposed to group these similar dysplasias in 'families' for two reasons: 1 The knowledge of developmental patterns shared by different genetic disorders cautions the diagnostician and encourages a two-step procedure: a) provisional recognition of a pattern and b) more careful analysis of the pattern to reach a final, specific diagnosis. 2 Families of bone dysplasias may be the result of similar pathogenetic mechanisms. Once the mechanism is discovered in one member of the family, a search for similar mechanisms in others may be rewarding. An example of such a pattern is dysostosis multiplex. It is found in a family of disorders caused by defects of complex carbohydrate degradation. The present study delineates four more patterns and their families: the achondroplasia pattern, spondyloepiphyseal dysplasia congenita pattern, the Larsen/OPD pattern and the Stickler/Kniest pattern.
Assuntos
Doenças do Desenvolvimento Ósseo/genética , Acondroplasia/classificação , Acondroplasia/diagnóstico por imagem , Acondroplasia/genética , Doenças do Desenvolvimento Ósseo/classificação , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Doenças do Tecido Conjuntivo/diagnóstico por imagem , Doenças do Tecido Conjuntivo/genética , Genes Dominantes , Genes Recessivos , Humanos , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Fenótipo , Radiografia , Síndrome/diagnóstico por imagem , Síndrome/genética , Displasia Tanatofórica/diagnóstico por imagem , Displasia Tanatofórica/genéticaRESUMO
A family is described in which two sibs of a consanguineous marriage have alopecia, convulsions, EEG anomalies and mental retardation. Although the children have significant features resembling those described by Moynahan, this syndrome appears to be different in the mode of inheritance and in other aspects (sensorineural hearing loss in the male, syndactyly in the female).