RESUMEN
Prospective screening for fragile X syndrome was carried out among 1,111 patients with mental retardation who attended the Genetic clinic. Using defined clinical criteria, 55 patients were selected for cytogenetic studies to detect folate sensitive fragile sites. Twenty patients were diagnosed to have the fragile X syndrome. The prevalence of fragile X (A) syndrome was 18 per 1,000 patients of both sexes with mental retardation, 2.8% among male patients with mental retardation, and 5.8% among subjects with nonspecific mental retardation.
Asunto(s)
Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Enfermedades en Gemelos/genética , Femenino , Síndrome del Cromosoma X Frágil/diagnóstico , Pruebas Genéticas , Humanos , India , Masculino , Discapacidad Intelectual/diagnósticoRESUMEN
The clinical features of 20 patients of Martin Bell syndrome were analyzed in order to derive diagnostic features in younger patients. The characteristic clinical features comprising long face, large ears and macro-orchidism were commoner in children more than 10 years old than in prepubertal children. This study shows that younger the patient, fewer the classical features exhibited. Hyperactivity was the most useful feature for diagnosis of the younger patient with Martin Bell syndrome.
Asunto(s)
Adolescente , Factores de Edad , Niño , Trastornos de la Conducta Infantil/etiología , Preescolar , Aberraciones Cromosómicas/genética , Trastornos de los Cromosomas , Femenino , Síndrome del Cromosoma X Frágil/complicaciones , Humanos , Masculino , Discapacidad Intelectual/etiologíaRESUMEN
Cytogenetic studies were carried out in 645 patients with Down syndrome. Free trisomy of chromosome 21 was present in 600 cases (93%). Translocation karyotypes were observed in 26 cases (4%). Seventeen patients (2.6%) had mosaicism. Two (0.3%) patients had additional karyotypic abnormalities along with trisomy 21.
Asunto(s)
Aberraciones Cromosómicas/epidemiología , Trastornos de los Cromosomas , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 15 , Cromosomas Humanos Par 21 , Cromosomas Humanos Par 22 , Síndrome de Down/epidemiología , Humanos , Cariotipificación , Translocación Genética/genéticaRESUMEN
Prenatal diagnosis of chromosomal disorders was carried out in 144 samples of amniotic fluid during 1986-1989. The commonest indication was pregnancy in women having a previous child with Down syndrome. Cultures were successful in 104 (72.2%) of 144 cases. Three (2.9%) abnormal karyotypes were detected. Of 53 women who had a previous child with Down syndrome, recurrence of trisomy 21 occur d in one (1.9%); while considering all abnormal karyotypes, there were three recurrences (2.9%).
Asunto(s)
Adulto , Amniocentesis/métodos , Aberraciones Cromosómicas/diagnóstico , Trastornos de los Cromosomas , Femenino , Humanos , Persona de Mediana Edad , EmbarazoRESUMEN
In a study on various factors which are known to influence the growth of amniotic fluid cells for successful cytogenetic analysis in 89 samples, amniotic fluid volume greater than 10 ml enhanced the chance of success (P = 0.0003). The presence of red blood cells reduced the success rate although this was not statistically significant. Among the techniques which proved successful were the use of closed culture method (plastic flasks in which 5% CO2 is blown), and the addition of Ultroser G, which enhances the adhesion and growth of amniotic fluid cells.