title: False deletion of the D15S986 maternal allele in a suspected case of Angelman syndrome.
abstract: BACKGROUND
  Angelman syndrome (AS) is a neurological disorder caused by genetic defects of the chromosome region 15q11-q13; some 70-80% of cases are due to deletions of the maternal allele, as the paternal copy is imprinted.
  
  
  METHODS
  A maternal deletion at D15S986 was reported in a suspected case of AS; this marker is located in intron 2 of the ATP10C gene, which has been implicated in the development of AS. A segment of ~830bp, including this marker and the primers used in routine genetic test, was cloned and sequenced.
  
  
  RESULTS
  A single nucleotide deletion (named ATP10C*c.760+3808delA, GenBank accession number HQ856823) was detected in the middle of the forward primer, leading to allele dropout. A large European population sample (N=363) was typed, and the detected variant was characterized as a novel polymorphism, with allele frequencies of 0.882 (TAT allele) and 0.118 (T-T allele).
  
  
  CONCLUSIONS
  An alternative primer set was developed, for which the segregation pattern of D15S986 in the proband extended family was normal. It can replace the currently used set.
authors.affiliation: Immunogenetic Laboratory, Cisanello Hospital, via Paradisa 2, 56124 Pisa, Italy. Electronic address: m.curcio@ao-pisa.toscana.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Curcio
authors.affiliation: Department of Physiological Science, University of Pisa, Pisa, Italy. Electronic address: sprex@biomed.unipi.it.
authors.forename: Silvano
authors.initials: S
authors.lastname: Presciuttini
mesh_terms: D000483:Alleles; D017204:Angelman Syndrome / Q000235:genetics*; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D005188:False Negative Reactions; D006801:Humans; D007223:Infant; D008297:Male; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion
keywords: ATP10C; Allele dropout; Angelman syndrome; D15S986; Genetic polymorphism