RESUMEN
Autistic disorder is a neurodevelopmental disorder with a complex genetic etiology. Observations of maternal duplications affecting chromosome 15q11-q13 in patients with autism and evidence for linkage and linkage disequilibrium to markers in this region in chromosomally normal autism families indicate the existence of a susceptibility locus. We have screened the families of the Collaborative Linkage Study of Autism for several markers spanning a candidate region covering approximately 2 Mb and including the Angelman syndrome gene (UBE3A) and a cluster of gamma-aminobutyric acid (GABA(A)) receptor subunit genes (GABRB3, GABRA5, and GABRG3). We found significant evidence for linkage disequilibrium at marker D15S122, located at the 5' end of UBE3A. This is the first report, to our knowledge, of linkage disequilibrium at UBE3A in autism families. Characterization of null alleles detected at D15S822 in the course of genetic studies of this region showed a small (approximately 5-kb) genomic deletion, which was present at somewhat higher frequencies in autism families than in controls.
Asunto(s)
Síndrome de Angelman/genética , Trastorno Autístico/genética , Ligasas/genética , Desequilibrio de Ligamiento , Alelos , Secuencia de Bases , Deleción Cromosómica , Cromosomas Humanos Par 15/genética , ADN/química , ADN/genética , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Subunidades de Proteína , Receptores de GABA-A/genética , Eliminación de Secuencia , Ubiquitina-Proteína LigasasRESUMEN
Amniotic fluid embolism is a rare, yet catastrophic event. In the United States it occurs in 1 per 20,000 to 30,000 births. With an 86% maternal mortality rate, amniotic fluid embolism is responsible for 10-15% of all maternal deaths. This article presents a case study of a CNM's experience with a maternal and fetal death resulting from an amniotic fluid embolism. Pathogenesis and appropriate management are also presented.