title: Molecular characterization of 18p deletions: evidence for a breakpoint cluster.
abstract: OBJECTIVE
  To determine the size and parental origin of the deletion in individuals with 18p- syndrome.
  
  
  METHODS
  Molecular and fluorescence in situ hybridization analyses of the pericentromeric region of chromosome 18 were performed on genomic DNA and chromosomes from study participants.
  
  
  RESULTS
  The majority of the breakpoints were located between markers D18S852 on 18p and D18S1149 on 18q, a distance of approximately 4 Mb. The parental origin of these deletions appears to be equally distributed, half maternally derived and half paternally derived.
  
  
  CONCLUSIONS
  The distributions of both the size and parental origin of the 18p deletions support the presence of a breakpoint cluster in the 18p- syndrome.
authors.affiliation: Department of Pediatrics, University of Texas Health Science Center, San Antonio, Texas 78229-7809, USA.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Schaub
authors.forename: Xavier T
authors.initials: XT
authors.lastname: Reveles
authors.forename: Jacques
authors.initials: J
authors.lastname: Baillargeon
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Leach
authors.forename: Jannine D
authors.initials: JD
authors.lastname: Cody
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics*; D000328:Adult; D002872:Chromosome Deletion; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D005220:Fathers; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008423:Maternal Age; D009035:Mothers; D010331:Paternal Age; D013577:Syndrome