Paternity/maternity Testing Research Paper

The history of paternity and maternity traces back to the 1800’s when they used the child’s iris pigment to identify the biological parents. The paternity or maternity quality was questioned when the child looked significantly different from the “alleged” biological parents. At that time very little was known about genes and how the offspring inherited them. Children were thought to have inherited some traits from the mother and father, but that they would inherit lets say brown eyes in the mom had brown eyes or green eyes if the dad had green eyes, but it was hard to explain if the child ended up with blue eyes when the biological parents at brown and green eyes.

Gregor Mendel was the first to form scientific theories of genetic inheritance. He theorised that half of a child’s traits came from the biological mother and half came from the biological father. This law would become the foundation for all paternity and maternity. “As research was done on the iris and genetics, scientists believed that the eye color was determined by the type of pigment in one’s iris. Since several genes contribute to the color of the iris, it is difficult to accurately predict the eye color of a child based on the eye colors of the parents. Therefore, it was never very useful to use eye colors to determine paternity.” (http://usimmigrationdnatesting.com). Almost a century later blood typing was discovered, this would improve the process of paternity and maternity testing. A new blood typing system called the ABO system was discovered. Human blood types were categorized as: A, AB, B, and O. This was based on the antigens found in the blood. It was then discovered that blood types were genetically inherited. My biological mother has O- blood and my biological father has O+, but I inherited O+.

In this scenario the O+ gene was stronger than the O- gene therefore I inherited the O+. After it was discovered that blood types were inherited scientists were able to predict the offspring's blood type. They were able to create charts that would be able to more accurately predict the blood type. Based on this scientists could used blood typing to determine the paternity or maternity of a child. However, because of many variables in the blood types and relationships, it is difficult to accurately prove biological relationships. “As the chart indicates, the power of exclusion (the power of a test to eliminate a certain percentage of the population from being biologically related to another tested individual) in a blood typing paternity test is only 30%. Blood typing is not a useful technique for determining paternity.” (http://usimmigrationdnatesting.com). Later in the 1930s, scientists would discover the Rh, Kell, and Duffy blood group systems. This system would be able to identify humans . The new systems were based on specific blood antigens genetically inherited from biological parents.This would make it very helpful in identifying possible blood relationships.“However, the serological tests based on the Rh, Kell, and Duffy blood group systems are not conclusive in identifying biological parents either.

The power of exclusion in a serological paternity test is only 40%, not effective enough to establish conclusive biological relationships.” (http://usimmigrationdnatesting.com). In the 1970’s the HLA or human leukocyte antigen was discovered by scientists. The HLA is a widespread protein in the human body cells. This would have an 80% success rate, but it was very dangerous and uncomfortable process, because large amounts of fresh blood samples were required. After the discovery of DNA structure a new technique formed. It was called Restriction Fragment Length Polymorphism (RFLP).