DNA profiling (also called DNA fingerprinting) is the process of determining an individual's DNA characteristics. DNA analysis intended to identify a species, rather than an individual, is called DNA barcoding. DNA profiling is a forensic technique in criminal investigations, comparing criminal suspects' profiles to DNA evidence so as to assess the likelihood of their involvement in the crime. It is also used in parentage testing, to establish immigration eligibility, and in genealogical and medical research. DNA profiling has also been used in the study of animal and plant populations in the fields of zoology, botany, and agriculture. Starting in the 1980s scientific advances allowed for the use of DNA as a material for the identification of an individual. The first patent covering the direct use of DNA variation for forensics was filed by Dr. Jeffrey Glassberg in 1983, based upon work he had done while at Rockefeller University in 1981. In the United Kingdom, Geneticist Sir Alec Jeffreys  independently developed a DNA profiling process in beginning in late 1984[9] while working in the Department of Genetics at the University of Leicester. The process, developed by Jeffreys in conjunction with Peter Gill and Dave Werrett of the Forensic Science Service (FSS), was first used forensically in the solving of the murder of two teenagers who had been raped and murdered in Narborough, Leicestershire in 1983 and 1986. In the murder inquiry, led by Detective David Baker, the DNA contained within blood samples obtained voluntarily from around 5,000 local men who willingly assisted Leicestershire Constabulary with the investigation, resulted in the exoneration of a man who had confessed to one of the crimes, and the subsequent conviction of Colin Pitchfork.