title: Forensic mitochondrial coding region analysis for increased discrimination using pyrosequencing technology.
abstract: Analysis of mitochondrial DNA (mtDNA) is very useful when nuclear DNA analysis fails due to degradation or insufficient amounts of DNA in forensic analysis. However, mtDNA analysis has a lower discrimination power compared to what can be obtained by nuclear DNA (nDNA) analysis, potentially resulting in multiple individuals showing identical mtDNA types in the HVI/HVII region. In this study, the increase in discrimination by analysis of mitochondrial coding regions has been evaluated for identical or similar HVI/HVII sequences. A pyrosequencing-based system for coding region analysis, comprising 17 pyrosequencing reactions performed on 15 PCR fragments, was utilised. This assay was evaluated in 135 samples, resulting in an average read length of 81 nucleotides in the pyrosequencing analysis. In the sample set, a total of 52 coding region SNPs were identified, of which 18 were singletons. In a group of 60 samples with 0 or 1 control region difference from the revised Cambridge reference sequence (rCRS), only 12 samples could not be resolved by at least two differences using the pyrosequencing assay. Thus, the use of this pyrosequencing-based coding region assay has the potential to substantially increase the discriminatory power of mtDNA analysis.
authors.affiliation: Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Andréasson
authors.forename: Martina
authors.initials: M
authors.lastname: Nilsson
authors.forename: Hanna
authors.initials: H
authors.lastname: Styrman
authors.forename: Ulf
authors.initials: U
authors.lastname: Pettersson
authors.forename: Marie
authors.initials: M
authors.lastname: Allen
mesh_terms: D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics* / Q000302:isolation & purification; D053803:Forensic Genetics / Q000379:methods*; D006239:Haplotypes; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial