DNA Polymorphisms in Forensic Science

DNA Polymorphisms in Forensic Science

• Primary Purpose: To distinguish and identify individuals based on unique, heritable DNA variations.

Methods of Detection

• PCR-based methods: Polymerase Chain Reaction is the most common method for detecting DNA polymorphisms, amplifying specific DNA regions for analysis.

Alleles

• Alternate forms of a gene: An individual inherits two alleles, one from each parent.

Single Nucleotide Polymorphisms (SNPs)

• Single base pair differences: DNA polymorphisms involving a change at a single nucleotide base.

Assisting Criminal Investigations

• Individual identification: Matching DNA profiles from crime scenes to suspects or victims.
• Paternity testing: Establishing biological relationships.
• Population genetics: Studying human ancestry and migration patterns.

DNA Polymorphisms in Forensic Science

• DNA polymorphisms are variations in DNA sequences that differentiate individuals, making them valuable in forensic science.

Applications of DNA Polymorphisms in Forensic Science

• Individual identification: DNA polymorphisms provide a unique genetic fingerprint for each person, aiding in the identification of suspects or victims.
• Paternity testing: Comparing polymorphisms between a child and potential father establishes biological relationships.
• Criminal investigations: DNA evidence from crime scenes can be matched to suspects using polymorphism analysis.

Detecting DNA Polymorphisms

• Polymerase chain reaction (PCR): PCR amplifies specific DNA regions containing polymorphisms, making them detectable.

Alleles

• Alleles are alternative forms of a gene at a specific locus (location on a chromosome) that determine traits.

Single Nucleotide Polymorphisms (SNPs)

• Single Nucleotide Polymorphisms (SNPs): are the most common type of genetic variation, occurring when a single nucleotide (A, T, C, or G) differs between individuals at a specific location in the genome.

How DNA Polymorphisms Assist in Criminal Investigations

• DNA evidence collected from crime scenes (e.g., blood, saliva, hair) is compared to suspects' DNA profiles using polymorphism analysis.
• Matching DNA profiles: A strong match between crime scene DNA and a suspect's DNA provides compelling evidence linking the suspect to the crime.

This quiz explores the role of DNA polymorphisms in forensic science, including their application in criminal investigations and methods of detection. You will also learn about key concepts such as alleles and single nucleotide polymorphisms (SNPs). Test your knowledge on how these genetic variations are pivotal in solving crimes.