Lecture 13 Future of Forensic Biology

DNA Methylation Assays

Techniques used to identify bodily fluids based on DNA methylation patterns.

Methyltransferase (DNMT)

An enzyme that converts cytosine to 5-methylcytosine in DNA.

Tissue-specific differentially methylated regions (TDMRs)

Regions of DNA where methylation patterns vary between different tissue types, useful for identifying specific cells.

Methylation-sensitive restriction enzyme digestion (MSRE-PCR)

A method for detecting DNA methylation by using enzymes that can cleave only unmethylated DNA.

Bisulfite sequencing

Technique that involves converting unmethylated cytosines to uracil, allowing for the detection of methylation status after PCR.

Methyl-DNA immunoprecipitation (MeDIP)

A method that uses antibodies to capture methylated DNA regions for further analysis.

mRNA-based assays

Forensic techniques that analyze tissue-specific gene expression for bodily fluid identification.

microRNA (miRNA)

Small non-coding RNA molecules that regulate gene expression and can be used for identifying different bodily fluids.

Top-down proteomics

Technique that analyzes intact proteins directly without prior digestion.

Bottom-up proteomics

Method that involves digesting proteins into smaller peptides before analysis.

Metagenomic approach

Analysis of a complete microbial community to identify predominant microbial species in a sample.

Nondestructive assays

Techniques for identifying bodily fluids that do not consume or damage the sample.

Fluorescence spectroscopy

A nondestructive technique that uses the emission of light to identify materials.

Raman spectroscopy

An analytical technique that determines molecular composition through inelastic scattering of monochromatic light.

CpG dinucleotide sequence

A DNA region where a cytosine nucleotide is followed by a guanine nucleotide; often a site for methylation.