Impact of the Sequencing Method on the Detection and Interpretation of Mitochondrial DNA Length Heteroplasmy

Publication date: Available online 10 November 2019Source: Forensic Science International: GeneticsAuthor(s): Kimberly Sturk-Andreaggi, Walther Parson, Marie Allen, Charla MarshallAbstractAdvancements in sequencing technologies allow for rapid and efficient analysis of mitochondrial DNA (mtDNA) in forensic laboratories, which is particularly beneficial for specimens with limited nuclear DNA. Next generation sequencing (NGS) offers higher throughput and sensitivity over traditional Sanger-type sequencing (STS) as well as the ability to quantitatively analyze the data. Changes in sample preparation, sequencing method and analysis required for NGS may alter the mtDNA haplotypes compared to previously generated STS data. Thus, the present study aimed to characterize the impact of different sequencing workflows on the detection and interpretation of length heteroplasmy (LHP), a particularly complicated aspect of mtDNA analysis. Whole mtDNA genome (mitogenome) data were generated for 16 high-quality samples using well-established Illumina and Ion methods, and the NGS data were compared to previously-generated STS mtDNA control region data. Although the mitogenome haplotypes were concordant with the exception of length and low-level variants (<30% variant frequency), LHP in the hypervariable segment (HVS) polycytosine regions (C-tracts) differed across sequencing methods. Consistent with previous studies, LHP in HVS1 was observed in samples with nine or more consecutive cytosine...
Source: Forensic Science International: Genetics - Category: Forensic Medicine Source Type: research