RESUMEN
In certain autosomal recessive disorders there is suggestive evidence that heterozygous carriers may have some selective advantage over normal homozygotes. These include, for example, cystic fibrosis, Tay-Sachs disease and phenylketonuria. The best example so far, however, is that of significant heterozygous advantage in sickle-cell anaemia with increased resistance to falciparum malaria.
Asunto(s)
Heterocigoto , Distrofias Musculares/genética , Homocigoto , Humanos , Factores ProtectoresRESUMEN
Emery-Dreifuss muscular dystrophy (EDMD) was delineated as a separate form of muscular dystrophy nearly 40 years ago, based on the distinctive clinical features of early contractures and humero-peroneal weakness, and cardiac conduction defects. The gene, STA at Xq28, for the commoner X-linked EDMD encodes a 34 kD nuclear membrane protein designated 'emerin', and in almost all cases on immunostaining is absent in muscle, skin fibroblasts, leucocytes and even exfoliative buccal cells, and a mosaic pattern in female carriers. The gene, LMNA at 1q21, for the autosomal dominant Emery-Dreifuss muscular dystrophy encodes other nuclear membrane proteins, lamins A/C. The diagnosis (at present) depends on mutation analysis rather than protein immunohistochemistry. It is still not at all clear how defects in these nuclear membrane proteins are related to the phenotype, even less clear that LMNA mutations can also be associated with familial dilated cardiomyopathy with no weakness, and even familial partial lipodystrophy with diabetes mellitus and coronary heart disease! What began as clinical studies in a relatively rare form of dystrophy has progressed to detailed research into the functions of nuclear membrane proteins particularly in regard to various forms of heart disease.
Asunto(s)
Distrofia Muscular de Emery-Dreifuss/genética , Distrofia Muscular de Emery-Dreifuss/fisiopatología , Humanos , Estudios RetrospectivosAsunto(s)
Medicina en las Artes , Pinturas/historia , Historia del Siglo XVII , Visita Domiciliaria , Humanos , Países BajosAsunto(s)
Personajes , Medicina en las Artes , Pinturas/historia , Anomalías Congénitas/historia , Oftalmopatías/historia , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Humanos , Trastornos Mentales/historia , Enfermedades del Sistema Nervioso/historia , Trastornos de la Visión/historiaRESUMEN
Many artists have depicted genetic disorders in portrait paintings. In some instances such disorders can be identified in self-portraits, most notably the tetralogy of Fallot in the Dutch painter Dick Ket, or in portraits of the famous, such as the Habsburg jaw in the Emperor Charles V. But it is in other portraits that most examples can be found, such as the different types of dwarfism depicted by Velázquez. A table listing over 70 examples is provided.
Asunto(s)
Enfermedades Genéticas Congénitas/historia , Medicina en las Artes , Retratos como Asunto , Personajes , Femenino , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , MasculinoRESUMEN
Though the molecular and biochemical bases of Duchenne muscular dystrophy are known, many questions still remain unanswered. They range from the nature and cause of gene deletions to the relationship between dystrophin defects and the clinical phenotype, both in affected males and female carriers. These questions are discussed in the light of recent developments.