DNA Profilling

In Glogpedia

by LittenP4G7
Last updated 5 years ago

Discipline:
Science
Subject:
Biology
Grade:
10

Toggle fullscreen Print glog
DNA Profilling

First Time: In 1987, Colin Pitchfork was convicted when his semen matched the samples taken from two raped and murdered girls.Fame and Misfourtune: In 1995, OJ Simpson was on trial for the murder of his ex-wife and her friend. He was found not guilty due to the poor treatment of the DNA samples while in Los Angeles Police Department.

1. Collect sample and extract DNA: Analysts only need 100 micrograms to make a DNA profile from a crime scene. 2. Amplify the telltale regions: Analysts use Polymerase Chain Reaction (PCR) to make copies of sample's DNA regions. 3. Count the repeats: During PCR, fluorescent dyes attach to Short Tandem Repeats (STR: four or five base long DNA units) so they can be distinguished between others during gel electrophoresis. After gel electrophoresis, it is easy for analysts to calculate the size of the STR region and number of repeats in each site. 4. Conviction: To arrest a suspect, 13 STR regions must match the 13 STR regions at the crime scene. It is a 1 in a billion chance that the system is wrong

DNA Profiling

Real Life Stories

Process

Tie In:We studied DNA in multiple units and even did a lab on alteration of it. You know basic structures and the definition of DNA (contains genetic instructions for development and function of living things) Forensic analysts use DNA to identify subjects in a crime.

Buy In: DNA evidence is crucial to crime investigations. This development in technology created a DNA database consisting of convicted offenders that are likely to commit crimes again. This has reduced crime rates, incarcerated violent criminals and makes streets safer for you!


Comments

    There are no comments for this Glog.