An overview of autosomal STRs and identity SNPs in a Norwegian population using massively parallel sequencing.

Publisher: Elsevier Country of Publication: Netherlands NLM ID: 101317016 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1878-0326 (Electronic) Linking ISSN: 18724973 NLM ISO Abbreviation: Forensic Sci Int Genet Subsets: MEDLINE

Original Publication: Amsterdam : Elsevier

Polymorphism, Single Nucleotide* ; High-Throughput Nucleotide Sequencing* ; Gene Frequency* ; Microsatellite Repeats* ; Genetics, Population* ; DNA Fingerprinting*; Humans ; Norway ; Sequence Analysis, DNA ; Likelihood Functions ; Genotype

In recent years, probabilistic genotyping software has been adapted for the analysis of massively parallel sequencing (MPS) forensic data. Likelihood ratios (LR) are based on allele frequencies selected from populations of interest. This study provides an outline of sequence-based (SB) allele frequencies for autosomal short tandem repeats (aSTRs) and identity single nucleotide polymorphisms (iSNPs) in 371 individuals from Southern Norway. 27 aSTRs and 94 iSNPs were previously analysed with the ForenSeq™ DNA Signature Prep Kit (Verogen). The number of alleles with frequencies less than 0.05 for sequenced-based alleles was 4.6 times higher than for length-based alleles. Consistent with previous studies, it was observed that sequence-based data (both with and without flanks) exhibited higher allele diversity compared to length-based (LB) data; random match probabilities were lower for SB alleles confirming their advantage to discriminate between individuals. Two alleles in markers D22S1045 and Penta D were observed with SNPs in the 3´ flanking region, which have not been reported before. Also, a novel SNP with a minor allele frequency (MAF) of 0.001, was found in marker TH01. The impact of the sample size on minor allele frequency (MAF) values was studied in 88 iSNPs from Southern Norway (n = 371). The findings were then compared to a larger Norwegian population dataset (n = 15,769). The results showed that the smaller Southern Norway dataset provided similar results, and it was a representative sample. Population structure was analyzed for regions within Southern Norway; F ST estimates for aSTR and iSNPs did not indicate any genetic structure. Finally, we investigated the genetic differences between Southern Norway and two other populations: Northern Norway and Denmark. Allele frequencies between these populations were compared, and we found no significant frequency differences (p-values > 0.0001). We also calculated the pairwise F ST values per marker and comparisons between Southern and Northern Norway showed small differences. In contrast, the comparisons between Southern Norway and Denmark showed higher F ST values for some markers, possibly driven by distinct alleles that were present in only one of the populations. In summary, we propose that allele frequencies from each population considered in this study could be used interchangeably to calculate genotype probabilities.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Keywords: Allele frequencies; Autosomal STRs; Identity SNPs; Massively parallel sequencing; Norwegian population; Population genetics

Date Created: 20240511 Date Completed: 20240616 Latest Revision: 20240616

20240617

10.1016/j.fsigen.2024.103057

38733649