Questions of paternity presented a challenge to potential parents and researchers for many years. ABO phenotypes were used during the first half of the 20th century, the problem was that the blood group information of ABO only excluded potential paternity, but not confirmed the paternal relationship. Over the next few decades, the effectiveness of paternity testing was increased by additional blood markers, such as MN antigens, Rh antigens, and HLAs. But there was still room for errors. Sequencing techniques a DNA analysis presented a new look at people's genomes in the 1980s and 1990s.
Parental testing is considered to be genetic fingerprinting which aims to determine a parent and a child have any relationship, or other family relationships. The test gives genetic proof whether a man is a biological father of a child. In spite of the fact that genetic testing is the most reliable standard method, there also exist older methods, such as analysis of various other proteins and enzymes, ABO blood group typing, and using human leukocyte antigen antigens. The paternity test is based on the comparison of the genetic profiles of the child and alleged father.
Paternity is investigated with the help of genetic technology. DNA is the basis of paternity cases. To distinguish between individuals by using their DNA samples, scientists use such techniques as DNA testing, DNA profiling, DNA typing, and genetic fingerprinting. DNA fingerprinting is considered to be a test that identifies and evaluates the genetic information (called DNA or deoxyribonucleic acid) which is in a person’s cells. DNA fingerprinting needs only a small sample of cells as the root of a hair or a drop of blood (DNA Fingerprinting).Genetic fingerprints exist in bone, blood, saliva, hair follicles, semen, sweat, and skin. Being the same in every cell, they retain the distinctiveness throughout the whole life of a person. Our cells contain 23 chromosomes (called DNA packets) from the mother and the same number from the father.
Genetic fingerprinting involves the fragment separation according to their size, DNA extraction, enzyme usage in order to cut it into fragments (some fragments will contain mini satellites), and fragments treatment with a radioactive probe to identify motifs and capture them on X-ray film. The result is a striped pattern (over 30 stripes) which resembles a bar code (Genetic fingerprinting explained). It is carried out with the help of such methods as Polymerase Chain Reaction, Restriction Fragment Length Polymorphism, and Amplified Fragment Length Polymorphism. Mitochondrial analysis and Y-chromosome analysis are also among popular DNA fingerprinting techniques.
Human DNA is 99% identical between individuals, and only 1% may be different enabling scientists to distinguish identity. One of the usages of DNA fingerprinting is our heredity probe. We inherit base pair arrangements from our parents. The relatedness probability is generated though the comparison of the banding patterns of a parent and a child. Thus, two similar patterns indicate kinship relations between people.
Genetic fingerprinting is considered to be a more accurate method of identification than blood typing, fingerprinting, or any other procedure. Helping to verify the parentage, genetic fingerprinting cannot definitely say whether the person undergoing the test is the father or the mother. But it can certainly tell if any of them is not the parent of a child.
It is rather difficult to make distinguishing between two people as the majority of human’s DNA matches exactly of any other human. As DNA fingerprinting uses a specific type of DNA sequence, which is known as a microsatellite (a short piece of DNA), it makes identification much easier. Comparison of a number of microsatellites gives the opportunity to identify a person relatively easily.