title: Small nuclear ribonucleoprotein polypeptide N quantitative methylation analysis in infants with central hypotonia.
abstract: Central hypotonic is one of the most difficult issues in neurology, ruling out neurogenetic syndromic causes is critical, Prader-Willi syndrome (PWS) it is the most frequent genetic syndrome, it is caused by the loss of expression of the paternal allele in a group of imprinted genes within 15q11-q13, and is characterized by severe prenatal and postnatal hypotonia. SNURF-SNRPN gene methylation detects 99% of the cases but fluorescent in situ hybridization (FISH) analysis is necessary to confirm chromosome microdeletions. The advantage of SNRP-quantitative strategy of methylated alleles is that it makes it possible to make the diagnosis and identify deletions and mosaicism in one reaction. In infants clinical diagnosis is difficult. It has been proposed that around 40% of hypotonic patients have PWS but an accurate percentage has not been established. Twenty-four central hypotonic infants were studied by this molecular strategy, showing 41.5% with the disease. This molecular approach also permitted calculation of gene dosage and detection of those cases with microdeletion.
authors.affiliation: Department of Human Genetics, Hospital General de México/Facultad de Medicina Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors.forename: Nayelli
authors.initials: N
authors.lastname: Nájera
authors.forename: Lourdes
authors.initials: L
authors.lastname: González
authors.forename: Javier
authors.initials: J
authors.lastname: Pérez Durand
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ruíz
authors.forename: Nayely
authors.initials: N
authors.lastname: Garibay
authors.forename: Yadira
authors.initials: Y
authors.lastname: Pastrana
authors.forename: Eduardo
authors.initials: E
authors.lastname: Barragan
authors.forename: Rosa Eréndira
authors.initials: RE
authors.lastname: Durán-R
authors.forename: Gloria
authors.initials: G
authors.lastname: Queipo
mesh_terms: D002675:Child, Preschool; D002872:Chromosome Deletion; D019175:DNA Methylation; D003937:Diagnosis, Differential; D018628:Gene Dosage; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009123:Muscle Hypotonia / Q000097:blood / Q000209:etiology* / Q000235:genetics / Q000378:metabolism; D011218:Prader-Willi Syndrome / Q000175:diagnosis / Q000503:physiopathology; D055517:snRNP Core Proteins / Q000235:genetics*
chemical_list: C526417:SNRPN protein, human; D055517:snRNP Core Proteins