Parallel sequencing of 170 STR and 132 SNP markers using the FGID forensic four-in-one DNA typing kit on the DNBSEQ-G99RS platform

Massive parallel sequencing (MPS) has rapidly emerged as a promising technique for forensic DNA typing due to its capacity to simultaneously detect numerous genetic markers and samples in a single reaction, allowing the direct acquisition of sequence information. In this current investigation, the FGID forensic four-in-one DNA typing kit was employed on the DNBSEQ-G99RS high-throughput sequencing platform to simultaneously analyse two types of forensic genetic markers-short tandem repeat (STR) and single nucleotide polymorphism (SNP). A total of 306 DNA markers, comprising Amelogenin, 66 autosomal STR (A-STR) loci, 29 X chromosomal STR (X-STR) loci, 75 Y chromosomal STR (Y-STR) loci, and 135 SNP (132 A-SNP and 3 Y-SNP) loci, were genotyped for 100 unrelated individual samples (50 males and 50 females). As a result, sequence-based STR typing identified 940 alleles on A-STRs, 378 alleles on X-STRs, and 519 alleles on Y-STRs. In comparison with length-based alleles, the number of unique alleles based on sequence increased by 58.18%. Additionally, 97 new sequence variations were observed at 29 STR loci, and MPS sequence information was obtained for the first time at 42 STR loci. Furthermore, when utilizing sequence-based data, forensic parameters exhibited a notable increase in combined power of discrimination (CPD) and combined power of exclusion for A-STR, a slight increase in CPD and combined mean exclusion chance for X-STR, and a marginal increase in discrimination capacity for Y-STR. Moreover, information data for 132 A-SNPs were acquired. As anticipated, our findings highlight the advantages of MPS in forensic genetic applications while contributing novel genetic data for Asian populations in forensic practice.