title: DNA methylation analysis with respect to prenatal diagnosis of the Angelman and Prader-Willi syndromes and imprinting.
abstract: The Angelman (AS) and Prader-Willi syndromes (PWS) are clinically distinct neurobehavioural syndromes resulting from loss of maternal (AS) or paternal contributions (PWS) of imprinted genes within the chromosomal 15q11-q13 region. The molecular diagnosis of both syndromes can be made by a variety of techniques, including DNA methylation, DNA polymorphism and molecular cytogenetic analyses. DNA methylation analysis at three major loci (ZNF127, PW71 and 5' SNRPN) has been successfully used for the postnatal diagnosis of AS and PWS. Methylation analysis, in contrast to other techniques, can reliably be used to diagnose all three major molecular classes (deletion, uniparental disomy and imprinting mutation) of PWS, and three of the four major classes of AS. In this study we demonstrate that methylation analysis can also be successfully used in prenatal diagnosis, by examining specimens obtained from amniocentesis and chorionic villus sampling. Correct prenatal diagnoses were obtained in 24 out of 24 samples using the 5' SNRPN locus; 4 out of 15 using the ZNF127 locus; and 10 out of 18 using the PW71 locus. Therefore, our data indicate that although the DNA methylation imprints of ZNF127 and 5' SNRPN arise in the germline and are present in brain, only 5' SNRPN maintains the imprint in tissues suitable for the prenatal diagnosis of AS and PWS.
authors.affiliation: Department of Biochemistry and Molecular Biology and Center for Mammalian Genetics, University of Florida College of Medicine, Gainesville, FL 32610, USA.
authors.forename: C C
authors.initials: CC
authors.lastname: Glenn
authors.forename: G
authors.initials: G
authors.lastname: Deng
authors.forename: R C
authors.initials: RC
authors.lastname: Michaelis
authors.forename: J
authors.initials: J
authors.lastname: Tarleton
authors.forename: M C
authors.initials: MC
authors.lastname: Phelan
authors.forename: L
authors.initials: L
authors.lastname: Surh
authors.forename: T P
authors.initials: TP
authors.lastname: Yang
authors.forename: D J
authors.initials: DJ
authors.lastname: Driscoll
mesh_terms: D000649:Amniocentesis; D017204:Angelman Syndrome / Q000175:diagnosis* / Q000235:genetics; D015193:Chorionic Villi Sampling; D019175:DNA Methylation; D015247:Deoxyribonuclease HindIII / Q000378:metabolism; D019003:Deoxyribonuclease HpaII / Q000378:metabolism; D005260:Female; D018392:Genomic Imprinting; D006801:Humans; D009154:Mutation; D011218:Prader-Willi Syndrome / Q000175:diagnosis* / Q000235:genetics; D011247:Pregnancy; D011296:Prenatal Diagnosis
chemical_list: D015247:Deoxyribonuclease HindIII; D019003:Deoxyribonuclease HpaII