Forensics – interesting facts

Here are some interesting facts about forensics and DNA:

• New Zealand was the second country in the world to establish a databank of DNA profiles.
  Find out more about New Zealand's DNA Databank.
• Your DNA is unique from your brothers and sisters because trillions of different combinations of your parents’ DNA are possible.
• Koalas have fingerprints that are almost indistinguishable from human fingerprints.
• Identical twins have identical DNA profiles because they develop from a single fertilised egg that splits into two.
  Find out more about twins.

• You leave a trail behind you everywhere you go. The trail is made up of hairs, cells and body fluids.
• DNA profiling has proven that an unusual bear shot in Canada’s Northwest was actually a cross between a grizzly bear and a polar bear.
• When feeling the texture of a surface, the ridges in our skin, which are used for fingerprinting, heighten the intensity of stimulation of our nerve endings.
  Find out more about skin and touch.
• No two fingerprints have ever been found alike.

• The study of skin markings or patterns on fingers, hands and feet, used for fingerprinting or footprinting, is called dermatoglyphics.
• The first criminal fingerprint identification was made in 1892 by Juan Vucetich. It proved that a mother had killed her sons.
• Luminol is used at crime scenes to detect small amounts of blood. It reacts with iron in the haemoglobin and emits a blue light.
• DNA profiling was used to identify the bodies of the Russian royal family who were murdered during the Russian Revolution in 1917.
• DNA profiling was first performed by Sir Alec Jeffreys in England in 1984 and was introduced into New Zealand in the late 1980s.
  Find out more about DNA profiling and Forensics and DNA.
• DNA from a person’s body, from their skin, blood or saliva, is always the same.
• Soil samples from clothes can be matched to crime scenes by profiling the DNA of microbes in the soil.

• Bare footprints are unique to an individual in the same way that fingerprints are.
• DNA is often found on half-eaten snacks or drink cans left behind at house burglaries.
• DNA has been found in 400,000-year-old plants preserved in ice in Siberia.
• The chance of two people having an identical DNA profile is 1 in 10 billion – except where they are identical twins.
• Polymerase chain reaction (PCR) allows DNA to be identified from tiny samples – a single molecule of DNA can be enough for PCR amplification.
• The common house mouse appears all over the world. However scientists can tell where the mouse came from by the pollen caught in its fur.
• By entering a crime scene just after a shooting, you can be covered with more gunshot residue than a shooter who runs away immediately.