DNA

DNA is a tightly wrapped into 23 pairs of chromosomes. One of the chromosomes pairs comes from mother and other one from mother.DNA is present in almost all cells in the body.in late 80s,Alec Jerrreys of Leicester University discovered that genetic markers in the DNA were as unique to each individual.as a fingerprint.he formed bar-code like pattern on X-ray film.one of the first crimes to be solved using this technique was the rape and murder of a 15 year old girl in 1983 in England.the testing process itself continues to be refined to make it quicker, more efficient and easier to handle.Even a minute sample-like a single stranged of hair and tiny bits of skin –are enough for a DNA match to done.