title: Prader-Willi-like phenotypes: a systematic review of their chromosomal abnormalities.
abstract: Prader-Willi syndrome (PWS) is caused by the lack of expression of genes located on paternal chromosome 15q11-q13. This lack of gene expression may be due to a deletion in this chromosomal segment, to maternal uniparental disomy of chromosome 15, or to a defect in the imprinting center on 15q11-q13. PWS is characterized by hypotonia during the neonatal stage and in childhood, accompanied by a delay in neuropsychomotor development. Overeating, obesity, and mental deficiency arise later on. The syndrome has a clinical overlap with other diseases, which makes it difficult to accurately diagnose. The purpose of this article is to review the Prader-Willi-like phenotype in the scientific literature from 2000 to 2013, i.e., to review the cases of PWS caused by chromosomal abnormalities different from those found on chromosome 15. A search was carried out using the "National Center for Biotechnology Information" (www.pubmed.com) and "Scientific Electronic Library Online (www.scielo.br) databases and combinations of key words such as "Prader-Willi-like phenotype" and "Prader-Willi syndrome phenotype". Editorials, letters, reviews, and guidelines were excluded. Articles chosen contained descriptions of patients diagnosed with the PWS phenotype but who were negative for alterations on 15q11-q13. Our search found 643 articles about PWS, but only 14 of these matched with the Prader-Willi-like phenotype and with the selected years of publication (2000-2013). If two or more articles reported the same chromosomal alterations for Prader-Willi-like phenotype, the most recent was chosen. Twelve articles of 14 were case reports and 2 reported series of cases.
authors.affiliation: Programa de Pós-Graduação em Neurologia, Hospital Universitário Gafrée e Guinle, Rio de Janeiro, RJ, Brasil.
authors.forename: C F
authors.initials: CF
authors.lastname: Rocha
authors.affiliation: Programa de Pós-Graduação em Neurologia, Hospital Universitário Gafrée e Guinle, Rio de Janeiro, RJ, Brasil clapaiva1@gmail.com.
authors.forename: C L A
authors.initials: CL
authors.lastname: Paiva
mesh_terms: D002869:Chromosome Aberrations; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D010641:Phenotype; D011218:Prader-Willi Syndrome / Q000175:diagnosis* / Q000235:genetics*