1970s - HLA Testing
In the mid 1970s, scientists turned from blood typing to tissue typing. Scientists discovered the human leukocyte antigen (HLA), a protein prevalent in all of the body except the red blood cells. White blood cells in particular carry a high concentration of HLA. There are many different types of HLA, and these types vary between each person. Because of the high variability of HLA types between different people, HLA testing became a more powerful mode of paternity testing. The power of exclusion for HLA testing alone is 80% and coupled with blood typing and serological testing is close 90%.
Despite its more powerful ability to identify biological relationships, HLA testing is not an ideal technique. HLA testing requires a large blood sample that must be no older than a few days old. The collection process can be uncomfortable, making it dangerous for infants under the age of 6 months.
Introduction to DNA Testing History
1920s >> Blood Typing
1930s >> Serological Testing
1970s >> HLA Testing
1980s >> DNA Testing Using RFLP Technique
1990s >> DNA Testing Using PCR Technology