Forensic analysis of LCN DNA using sample concentration methods followed by miniSTR genotyping

Objective: To optimize low copy number (LCN) DNA analysis methods for forensic STR genotyping.

Methods: Two groups of DNA sample, extracted using either Magnetic bead method or Chelex-100 methods, were previously amplified with a Identifiler PCR Amplification kit, but no genotype was detected. The DNA samples were concentrated using either a drying method or the Microcon-100 method, then amplified using an miniFiler PCR Amplification kit and genotyped.

Results: Among the 127 DNA samples, 47 samples, previously extracted using the Magnetic bead method, were genotyped with 36% success rate. Eighty samples, previously extracted using the Chelex-100 method, were genotyped with 30% success rate.

Conclusions: The application of sample concentration methods and miniFiler kit can improve the success rate of LCN STR analysis.