[IDENTIFICATION OF COMINGLED TISSUE WITHIN A FORMALIN-FIXED PARAFFIN-EMBEDDED SAMPLE USING FORENSIC GENETICS - A TOOL...

Area of Science:

• Forensic Genetics
• Molecular Pathology
• Biopathology

Background:

• Formalin-fixed, paraffin-embedded (FFPE) tissue processing is standard for biopsy evaluation.
• Histopathology cannot detect cross-contamination of tissues from different patients.
• Forensic genetic procedures ensure reliable DNA profiles from degraded samples like FFPE tissues.

Purpose of the Study:

• To demonstrate the utility of forensic genetics in detecting FFPE tissue cross-contamination.
• To prevent misdiagnosis and inappropriate treatment due to sample mix-ups.

Main Methods:

• DNA extraction from FFPE tissue fragments.
• Short Tandem Repeat (STR) analysis for DNA profiling.
• Comparison of DNA profiles against patient reference samples.

Main Results:

• Initial DNA analysis of FFPE tissues matched the patient.
• Detection of minor additional alleles suggested a second contributor.
• Targeted DNA extraction from a specific lesion revealed a male DNA profile, confirming cross-contamination.

Conclusions:

• Forensic genetic analysis effectively identified cross-contamination in FFPE colon tissue.
• Collaboration between medical examiners and forensic labs is crucial for accurate diagnosis.
• Molecular techniques prevent misdiagnosis and ensure patient safety.