title: Reinvestigations of six unusual paternity cases by typing of autosomal single-nucleotide polymorphisms.
abstract: BACKGROUND
  In some relationship cases, the initial investigations of autosomal short tandem repeats (STRs) lead to an ambiguous conclusion and supplementary investigations become necessary.
  
  
  METHODS
  Six unusual paternity cases were previously investigated by other researchers and published as case work examples in forensic journals. Here, the cases were reinvestigated by typing the samples for 49 autosomal single-nucleotide polymorphisms (SNPs) using the SNPforID multiplex assay.
  
  
  RESULTS
  Three cases were solved by the SNP investigation without the need for any additional testing. In two cases, the SNP results supported the conclusions based on STRs. In the last case, the SNP results spoke in favor of paternity, and the combined paternity index based on autosomal STRs and SNPs was 12.3 billion. Nevertheless, the alleged father was excluded by X-chromosome typing.
  
  
  CONCLUSIONS
  The case work examples underline the importance of performing supplementary investigations, and they advocate for the implementation of several panels that may be used in the highly unusual cases. Panels with SNPs or other markers with low mutation probabilities are preferable as supplementary markers, because the risk of detecting (additional) mutations is very low.
authors.affiliation: Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark. claus.boersting@forensic.ku.dk
authors.forename: Claus
authors.initials: C
authors.lastname: Børsting
authors.forename: Niels
authors.initials: N
authors.lastname: Morling
mesh_terms: D016172:DNA Fingerprinting / Q000379:methods; D005220:Fathers; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D058889:Molecular Typing / Q000379:methods*; D009035:Mothers; D010287:Parent-Child Relations; D010334:Paternity; D020641:Polymorphism, Single Nucleotide
chemical_list: D005819:Genetic Markers