Mitochondrial DNA (mtDNA) sequence analysis as an additional tool for forensic identification purposes

When there is suspicion that the DNA in the sample is degraded, charred or insufficient for STR analysis in particular for forensic investigations, an alternative technique/approach that is commonly being employed and must be is mitochondrial DNA (mtDNA) sequence analysis-a valid and reliable tool for genetic characterization of forensic biological specimens. Apart from the commonly used materials for human identification, which include skin, blood, semen and saliva, mtDNA has been extracted from teeth, hair shafts, bone fragments and even human feces all of which often fail to yield results with nuclear DNA markers. Thus mtDNA which was for the first time demonstrated by electron microscopy has proved to be more robust than nDNA. The results of which are attributed to its high copy number per cell and resistance to extreme environmental conditions along with other special features including its haploid maternal mode of inheritance, high levels of diversity, lack of recombination, lack of introns and histones and rapid rate of evolution. MtDNA haplotypes which are uniparentally inherited therefore reflect information from a non-recombining maternal lineage that may be shared by numerous people within the maternal lineage. As a result, mtDNA data cannot be applied to the identification of individuals in the same way that analyses from recombining nuclear DNA markers can. The present study is aimed at providing an overview of mitochondrial DNA analysis that can aid in criminal justice delivery system particularly related to kidnapping, murder, disaster and missing person identity.