Characterization of a highly variable short tandem repeat polymorphism at the D2S1242 locus
B Reichenpfader1, R Zehner, M Klintschar
1Department of Forensic Medicine, Karl-Franzens-Universität, Graz, Austria. barbara.reichenpfader@kfunigraz.ac.at
Electrophoresis
|April 27, 1999
Summary
Forensic scientists evaluated the D2S1242 short tandem repeat (STR) locus using polymerase chain reaction (PCR) in 147 Austrians. This STR locus shows high discriminating power for forensic identification.
Area of Science:
- Forensic genetics
- Human population genetics
- Molecular biology
Background:
- Short tandem repeat (STR) loci are crucial for forensic DNA profiling.
- The D2S1242 locus requires thorough evaluation for its forensic applicability.
- Understanding population-specific genetic variation is key for accurate identification.
Purpose of the Study:
- To evaluate the forensic potential of the STR locus D2S1242.
- To determine the genetic variability and population data for D2S1242 in an Austrian population.
- To establish an allelic ladder for accurate genotyping.
Main Methods:
- Polymerase chain reaction (PCR) amplification of the D2S1242 locus.
- Analysis using native and denaturing polyacrylamide gel electrophoresis.
- Sequencing for allelic ladder construction and motif identification.
Main Results:
- The D2S1242 locus exhibited no deviations from Hardy-Weinberg expectations in 147 unrelated Austrians.
- High forensic performance metrics were observed: Mean Exclusion Chance (MEC) of 0.669 and Discriminating Power (DP) of 0.947.
- An allelic ladder with eight alleles (10-18 repeat units) was established, revealing GAAA and GAAG tetranucleotide repeat motifs.
Conclusions:
- The D2S1242 STR locus is a valuable marker for forensic identification in the Austrian population.
- The established allelic ladder and population data facilitate reliable forensic casework.
- The locus demonstrates robust genetic characteristics suitable for DNA profiling applications.
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