A comparative study on the typing difference between the Identifiler™ kit and three domestic genotyping kits

Objective To study the difference of DNA testing results between the Identifiler™ kit and three domestic genotyping kits. Methods 455 unrelated individuals of Han population in China were typed using the Identifiler™, DNA Typer™ 15, GoldenEye 16BT and AGCU17 + 1 kits respectively. The genotypes were compared at 11 mutual loci among these four kits, and those samples with inconsistent genotypes were further analyzed by sequencing. Results Total 4 samples were observed to have inconsistent genotypes in all 455 individuals with three domestic genotyping kits, and the frequency was 0. 88%. For these four samples, one allele dropout, one amplification imbalance, and two false tri-peak were observed at CSF1PO locus with the Typer™ 15 kit, D18S51 locus with the AGCU17 + 1 kit and D21S11 locus with the 16BT kit correspondingly. The results of sequence analysis showed that all of these differences were caused by point mutation except a false tri-peak sample was caused by replication slippage. Conclusion Compared with the Identifiler™ kit, occasional genotyping differences could happen to all of these three domestic genotyping kits, and we should pay more attention to them in practical case.