PubMed · 8136461
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
R Wilson, C R Leitch, J Roberts, C Jenkins, J H McKillop, J J Walker. 1993. Interleukin 8.. https://doi.org/10.3109/08916939309115757
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The RSH/Smith-Lemli-Opitz syndrome (RSH/SLOS) is a relatively common, autosomal recessive malformation syndrome comprising distinctive facial, limb and genital anomalies, and mental retardation. Most patients with a clinical diagnosis of RSH/SLOS have a defect of cholesterol biosynthesis at the level of 3beta-hydroxysteroid-delta7-reductase, resulting in a decreased level of cholesterol and an increased level of 7-dehydrocholesterol (7DHC) in body fluids and tissues. We report on our experience with the prenatal diagnosis of RSH/SLOS by quantitative sterol chromatography in amniotic fluid (AF) and chorionic villus (CV). Of 76 AF and nine CV samples analyzed for various indications, 20 were diagnostic of RSH/SLOS based on an increased level of 7DHC in the fluid or tissue. Of 39 fetuses at a 25% risk for RSH/SLOS, 10(25.6%) were affected. Twenty-nine pregnancies not known to be at risk for RSH/SLOS were studied because of either a fetal abnormality characteristic of RSH/SLOS detected by ultrasound, a low maternal serum uE3 level (MSuE3), or both. None of the pregnancies tested, because of a low MSuE3 but lacking a sonographic abnormality characteristic of RSH/SLOS, was affected. However, three of four pregnancies with a low MSuE3 and an RSH/SLOS-type fetal abnormality were positive. RSH/ SLOS was diagnosed in two additional pregnancies on which MSuE3 data were not available but in which fetal anomalies were identified. Of these five RSH/SLOS fetuses identified in pregnancies not otherwise at risk for RSH/SLOS, the presenting sonographic anomaly was either polydactyly, ambiguous genitalia, or both. Evaluation of the biochemical parameters and clinical severity of RSH/SLOS showed that there was an inverse correlation between clinical severity and both the level of AF 7DHC and the level of MSuE3. Based on these earlier and more extensive studies, we conclude that accurate prenatal diagnosis of RSH/ SLOS is possible by sterol analysis of AF and, most likely, CV specimens as well. Furthermore, our findings suggest that MSuE3 levels in combination with sonography may provide useful diagnostic and prognostic information in the absence of a family history of RSH/SLOS.
The polymerase chain reaction (PCR) offers new advances in prenatal genetic diagnosis particularly with limitations in amount of sample, turn-around time of results, and costs. However, maternal contamination is a concern in any fetal sampling, and even more so with PCR given its potential to detect at the level of a few cells. We report our experience with 53 matched pairs of direct and cultured amniocytes using three independent DNA markers amplified by PCR within the setting of a service molecular diagnostic laboratory. Despite 15/53 (30 per cent) of the amniotic fluids showing visible red blood cells prior to culturing, only 5/53 (9 per cent) showed trace PCR contamination. Of note, this was found on only one marker with a particularly robust PCR product of small size and at such a low level that it was unlikely to have resulted in ambiguous interpretation. One of the cultures also showed a similar type of contamination with this same marker. However, in addition, there were 2/53 (3.7 per cent) cultures which showed substantial maternal contamination detected by all three PCR markers, but not visualized on the originating direct samples. Our results suggest that the careful use of direct amniocytes for molecular genetic testing by PCR is reliable and reproducible in most cases.
This article describes a case of fetal trisomy 17 mosaicism found in amniotic fluid cells in one of two bichorial biamniotic twins without any sonographic anomaly. The extra chromosome 17 was absent from cord blood cells at birth but present on karyotype and in situ hybridization in cultured fibroblasts from skin biopsy. Clinical examination showed a few mild dysmorphic features and a moderate neurological involvement which may rather be related to prematurity. It therefore seemed important to obtain the karyotype on fibroblasts when a trisomic cell line was found in amniocentesis and not confirmed on blood lymphocytes, even in the absence of dysmorphic features. This should help to differentiate a real mosaic from a mosaic restricted to extra-fetal tissues.