The last several decades have seen a dramatic increase in both convictions and exonerations for various crimes as a result of advances in DNA sequencing technology. Let’s discover how DNA and Genetic Genealogy is used to solve crimes. When a suspect’s identification is unclear, law enforcement can enter the DNA profile from the crime scene into CODIS to determine whether it matches to any previously submitted profiles. A CODIS profile comparison can connect crimes and associate suspects with crime scenes.
The results of DNA fingerprinting are not always promising. There are new and upcoming technologies that can be used to help solve crimes in circumstances when DNA fingerprinting cannot be used.
Forensic genealogy is a new method that combines traditional genealogical research with DNA analysis to produce leads for criminal investigations. The Golden State Killer case is the most well-known case that has been solved via forensic genealogy.
A law enforcement agency (police force, sheriff’s office) hires a Genetic Sequencing Lab to assist in solving a cold case.
1. The lab analyses DNA recovered from crime scenes and creates a file with its distinct base sequence (adenine, cytosine, guanine, and thymine).
2. Analyzing the data involves looking at over 700,000 single nucleotide polymorphisms (SNPs), which are the most prevalent genetic variations among individuals.
3. Police DNA databases utilize a more basic short tandem repeat (STR) analysis, which only enables the identification of close relatives. Online genealogy services use SNP DNA analysis to locate distant relatives.
4. The Lab hired by law enforcement submits the data file to a genealogy website like GEDmatch. SNPs are evaluated against millions of additional samples. A list of individuals with DNA matches is provided by the genealogy service. GEDmatch and Family Tree DNA are the two databases that have been known to use for IGG (Investigative genetic genealogy) so far. A third database that functions involves the recovery, enrichment, and analysis of human DNA from minute amounts of forensic evidence that has been tainted or degraded. Othram, a company that does forensic genome sequencing, opened this forensic genome laboratory in December 2019 specifically to work on Law enforcement cases.