[STR profiling of genomic DNA from HE stained tissue sections]

Area of Science:

• Forensic science
• Molecular biology
• Histopathology

Context:

• Forensic investigations often rely on DNA analysis, but obtaining quality DNA from preserved tissue samples can be challenging.
• Hematoxylin and eosin (HE) staining is a common method for tissue preservation, but it can impact DNA integrity.
• Developing reliable DNA extraction and analysis protocols for stained tissues is crucial for advancing forensic casework.

Purpose:

• To establish a reliable Short Tandem Repeat (STR) analysis method for DNA extracted from HE-stained human tissue sections.
• To assess the efficacy of this protocol for forensic applications, particularly in identifying individuals from historical or archived samples.

Summary:

• Genomic DNA was successfully extracted from various HE-stained human tissues (heart, liver, lung, intestine) from autopsy cases.
• DNA quantitation and STR analysis were performed using TaqMan PCR and the Identifiler PCR Amplification kit, respectively.
• Sufficient DNA concentrations (>1 ng/µL) were obtained without PCR inhibition, though DNA degradation was noted in samples stored longer, impacting allele detection.

Impact:

• This method enables the analysis of valuable DNA evidence from archived and stained tissue samples, potentially solving cold cases.
• The findings highlight the importance of sample storage duration, as extended storage can lead to DNA degradation and reduced STR profile quality.
• The protocol provides a foundation for improving DNA profiling techniques in forensic science, especially when dealing with challenging sample types.