title: Prader-Willi syndrome: genetic tests and clinical findings.
abstract: Here we describe the genetic studies performed in 53 patients with the suspected diagnosis of Prader-Willi syndrome (PWS). PWS is characterized by neonatal hypotonia, hypogonadism, delayed psychomotor development, hyperphagia, obesity, short stature, small hands and feet, learning disabilities, and obsessive-compulsive behavior. Through the methylation analysis of the SNRPN gene, microsatellite studies of loci mapped within and outside the PWS/AS region, and fluorescence in situ hybridization (FISH) study, we confirmed the diagnosis in 35 patients: 27 with a paternal deletion, and 8 with maternal uniparental disomy (UPD). The clinical comparisons between deleted and UPD patients indicated that there were no major phenotype differences, except for a lower birth length observed in the UPD children. Our sample was composed of more girls than boys; UPD patients were diagnosed earlier than the deleted cohort (2(10/12) s. 7(9/12) years); and, in the deleted group, the boys were diagnosed earlier than the girls (5(2/12) vs. 7(8/12) years, respectively).
authors.affiliation: Department of Biology, Institute of Bioscience, University of São Paulo, Brazil. cfridman@ib.usp.br
authors.forename: C
authors.initials: C
authors.lastname: Fridman
authors.forename: M C
authors.initials: MC
authors.lastname: Varela
authors.forename: F
authors.initials: F
authors.lastname: Kok
authors.forename: N
authors.initials: N
authors.lastname: Setian
authors.forename: C P
authors.initials: CP
authors.lastname: Koiffmann
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D019175:DNA Methylation; D005260:Female; D005838:Genotype; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008214:Lymphocytes; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D010641:Phenotype; D011218:Prader-Willi Syndrome / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*; D017384:Sequence Deletion / Q000235:genetics