Reference sources: 1  Petwave.com â Obesity Problems. 2  Petwave.com â Dogs Health. 3  Petwave.com â Cancer Types.  Dog Time.com â 10 Most Serious Pet Diseases.
Only a small sample of cells is needed for DNA fingerprinting. A drop of blood or the root of a hair contains enough DNA for testing. Semen, hair, or skin scrapings are often used in criminal investigations. A person who has DNA fingerprinting done voluntarily usually provides a sample of blood taken from a vein.
DNA fingerprinting is done to: 1  Find out who a person's parents or siblings are. 2  This test also may be used to identify the parents of babies who were switched at birth.3  Solve crimes (forensic science).lood sample from a heel stick. If a DNA blood test is done on a baby, a heel stick will be done instead of a blood draw from a vein. For a heel stick blood sample, several drops of blood are collected from the heel of the baby. The skin of the heel is cleaned with alcohol and then pricked with a small, sterile lancet.