Systematic analysis of population studies performed with the ForenSeq™ DNA Signature Prep kit

Many forensic laboratories have conducted sequence-based population studies to support the integration of massively parallel sequencing (MPS). However, the data remain limited concerning African populations. MPS enhances allelic representation compared to CE methods. It is hypothesized that this increase will be more pronounced for African populations due to their greater genetic diversity. A systematic review and meta-analysis were conducted to compile data from population genetic studies using the ForenSeq™ DNA Signature Prep kit, frequently employed in forensic MPS population studies. The aim of the review was to gain insight into global forensic sequence-based population data, focusing on African and underrepresented populations. The search spanned three databases, resulting in 582 records, where 40 articles met inclusion criteria for the systematic review and 20 qualified for the meta-analysis. The meta-analysis aimed to quantify the increase in genetic variation in autosomal short tandem repeat (A-STR) markers using allele counts and random match probability (RMP). Most population studies were conducted in high-income countries (65%, 26/40), with none from Africa. Only 14 out of 40 studies included concordance data, with 13 of these reporting rates above 99%. The meta-analysis covered 35 population groups and found that of the 27 A-STR markers evaluated, mean allele counts increased by 53.08% from length-to-sequence-based analyses. African ancestry groups showed the highest increase in allele counts and the biggest reduction in RMP. Despite substantial genetic diversity in African populations, their representation in MPS studies is minimal. Addressing this gap is crucial to justify further research in African countries.