Forensic tri-allelic SNP genotyping using nanopore sequencing

One of the latest developments in next generation sequencing is Oxford Nanopore Technologies' (ONT) MinION sequencer. This miniature sequencer holds promising features that could be useful in the field of forensic genetics. We applied this technology for forensic sequencing in a pilot study to investigate its potential for human identification based on tri-allelic single nucleotide polymorphisms (SNPs). Using primers that were originally designed for a SNP multiplex PCR and CE, we developed a library preparation method suitable for nanopore sequencing, including a barcoding step. This allowed us to sequence multiple samples (three control samples and two GEDNAP samples) in a single sequencing run. Duplicate sequencing was performed using both the 1D and 1D2 chemistry. Despite the high systematic sequencing error rate, typical for nanopore sequencing, the analysis yielded partial forensic profiles with useful evidential value. Over all samples, the 1D data allowed correct genotyping of 78 out of 80 loci, whereas using the 1D2 data all but one locus could correctly be genotyped.