No abstract

Through bacterial cloning, a non-specific product co-amplified in a previous whole mitochondrial genome study of Canis lupus familiaris was identified as part of a Numt on chromosome 29 of the dog. Even though further analysis confirmed the fidelity of the mitochondrial genome sequencing results, it still highlighted the risk of Numt contamination. A computer-based search of the dog's nuclear genome for segments homologous to the mtDNA sequence revealed the extent of this risk. Over 150 Numts of various sizes were observed throughout all but two chromosomes, covering all positions of the mtDNA. One of the Numts on chromosome 11 even covered over 95 % of the entire dog mtDNA sequence. This comprehensive list of Numts was provided to assist researchers with the evaluation of dog mtDNA sequencing protocols for Numt co-amplification.

The identification of dog hair through mtDNA analysis has become increasingly important in the last 15 years, as it can provide associative evidence connecting victims and suspects. The evidential value of an mtDNA match between dog hair and its potential donor is determined by the random match probability of the haplotype. This probability is based on the haplotype’s population frequency estimate. Consequently, implementing a population study representative of the population relevant to the forensic case is vital to the correct evaluation of the evidence. This paper reviews numerous published dog mtDNA studies and shows that many of these studies vary widely in sampling strategies and data quality. Therefore, several features influencing the representativeness of a population sample are discussed. Moreover, recommendations are provided on how to set up a dog mtDNA population study and how to decide whether or not to include published data. This review emphasizes the need for improved dog mtDNA population data for forensic purposes, including targeting the entire mitochondrial genome. In particular, the creation of a publicly available database of qualitative dog mtDNA population studies would improve the genetic analysis of dog traces in forensic casework.