- Molecule that carries instructions for our development.
Genome = All our DNA
- Genome - made of chromosomes
- 23 pairs of chromosomes (22 autosomes + 1pair sex)
- 99.9% of our genomes are same from person to person
- Identical twins have same DNA, different fingerprints.
Chromosomes in pairs
- One from Mum
- One from Dad
Location on Chromosomes = LOCUS
Locus on one of the genes in chromosomes = ALLELE
Combination of alles at a locus = GENOTYPE
- If both CHROMOSOMES are same = HOMOZYGOUS
- If CHROMOSOMES differ = HETEROZYGOUS
Development of DNA
- 1900 - Blood groups discovered.
- 1915 - first blood tests developed (ABO types) and potential for typing blood investigated.
- 1940-50 - Other blood groups found.
- 1985 - Sir Alec Jeffreys publishes first DNA fingerprint
All cells except red blood cels have a nucleus therefore contain DNA
- Break open cell
- Remove proteins
- Revocer DNA
Disaster Victim ID
- Fragmented remains
- Mised remains
- Bodies badly degraded
- Need suitable reference sample for comparison
- Identify matching bodyparts
- ID by matching DNA profile to personal items
- ID by comparing to known relative
- Animal DNA can be used to link suspect to crime scene
- Species identification
National DNA Database
- Set up 1995
- Samples can be collected from anyone arrested
- DNA kept indefinitely
- Owned by ACPO
- Managed by Home Office