Short tandem repeat analysis in Japanese population

Area of Science:

• Forensic Genetics
• Molecular Biology
• Population Genetics

Background:

• Short tandem repeats (STRs), also known as microsatellites, are highly informative genetic markers.
• Their small allele size facilitates easy amplification via polymerase chain reaction (PCR), enabling high detection sensitivity.
• Multiplex PCR allows simultaneous amplification of multiple STR loci, increasing efficiency and reducing DNA requirements.

Purpose of the Study:

• To investigate the utility of 14 STR loci for individual identification in a Japanese population.
• To evaluate the effectiveness of three multiplex PCR kits for STR analysis.
• To establish the applicability of STR typing in forensic casework and paternity testing.

Main Methods:

• Genomic DNA extraction using SDS proteinase K or Chelex 100, followed by phenol/chloroform extraction.
• Amplification of 14 STR loci using three multiplex PCR kits: GenePrint PowerPlex 1.1, PowerPlex 2.2, and AmpF/STR Profiler.
• Electrophoresis on an ABI 377 sequencer and allele determination using GeneScan 2.0.2 software.

Main Results:

• Statistical parameters for the 14 STR loci indicated a high rate of informativeness.
• No significant deviation from Hardy-Weinberg equilibrium was detected in the studied Japanese population.
• The STR typing system demonstrated effectiveness for paternity testing and forensic identification, including rape cases.

Conclusions:

• The investigated STR system is a powerful tool for individual identification in forensic science.
• Multiplex PCR analysis of 14 STR loci provides substantial genetic information efficiently.
• This method is suitable for routine application in forensic casework and paternity testing.