Mitochondrial DNA analysis of acellular laboratory samples.

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• Acellular specimens, particularly in toxicology, often face challenges in source verification.
• Conventional genetic testing may not be suitable for confirming the origin of acellular samples.

Purpose of the Study:

• To evaluate the efficacy of mitochondrial DNA (mtDNA) over genomic DNA for source identification in acellular specimens.
• To develop a novel assay for accurate specimen source confirmation in toxicology.

Main Methods:

• Polymerase chain reaction (PCR) was used to amplify genomic and mitochondrial DNA (mtDNA) from various urine specimen types.
• Sequencing of mtDNA amplicons identified single nucleotide polymorphisms (SNPs).
• A real-time PCR assay utilizing fluorescence resonance energy transfer (FRET) probes was developed for SNP detection in the mtDNA control region.

Main Results:

• mtDNA amplicons demonstrated higher sensitivity and detection rates compared to genomic DNA across all tested sample sets.
• The developed FRET-based assay successfully identified specific mitochondrial genotypes.
• The assay proved effective in distinguishing between different specimen sources.

Conclusions:

• Mitochondrial DNA analysis offers a more sensitive approach for verifying the source of acellular specimens than genomic DNA.
• The developed FRET assay provides a feasible method for screening acellular laboratory specimens to detect mix-ups or confirm origins.
• This technique enhances the reliability of toxicology testing by ensuring specimen integrity.