genetic fingerprinting

• VNTRs

  variable number of tandem repeats

  • in introns
• process:

  collect DNA sample and amplify using PCR

  restriction endonuclease is used to cut the DNA

  gel electrophoresis (electric voltage) is used to separates along length and mass

  alkaline is added to separate double strand to make single-stranded;

  apply probe to single strand DNA Radioactive / fluorescent labelled 

  transfer to (nylon) membrane - using X rays/UV light to visualise
• uses of genetic fingerprinting

  forensic science, medical diagnosis, animal/plant breeding, population genetics
• forensic science

  suspects DNA left at the crime scene - used to identify suspects
• medical diagnosis

  establish genetic relationships - paternity tests