Introduction:
When a child is born he or she carries the DNA of both the parents. Both parents are equally responsible for the birth of the child. The man who has contributed his sperms to this child is considered to be the biological father. But there is another term called legal father, a legal father is the one who is recognized as the father of the child by the law. The legal father may not be the biological father of that child. The word paternity means legal fatherhood of the child. Every child has a biological father but not legal father. A legal father has the right to support the child financially, take care of the child etc.
In many societies it has been found that the child is born from unmarried parents, in this case this biological father is not considered as the legal father. Even if the name is written in the birth certificate then also he is not the legal parent of the child. He has to establish it with the help of law by recognition of parental (ROP) process and by court of law.
Paternity disputes occur when the father claims that he is not the biological father of that child and refuse to take the responsibility of the child, however the mother claims that the man is the biological father of her child. The question of disputed paternity may arise in cases of (Khaganwal; 2012):
- Illegitimacy
- Posthumous birth
- Suppositious child
- Nullity of marriage
- Divorce
- Inheritance of property
- Guardianship
- Maintenance
As we know that only a legitimate child can inherit the property. In case of Lohi and Radhika Singh the Supreme Courted states that if a man and woman who are unmarried and stay together for a long time and behave like a married couple then there is presumption of a valid marriage and the child born will be legitimate and will have the right to inheritance and succession.
Under Section 3(57) of the General Clauses Act, 1897, the definition of son includes an adopted son and under Section 12 of the Hindu Adoption and Maintenance Act, 1956, an adopted son or daughter is entitled to succeed to the estate of his adoptive parents.
Approaches to solve disputed paternity
Disputed paternity can be solved through different approaches:
- Morphological approach between the child and parent.
- Serological approach
- Immunological approach through Human Leukocyte Antigen (HLA) typing
- DNA typing (DNA Profile) which include Variable number tandem repeats (VNTR), short tandem repeats (STR), polymerase chain reaction (PCR).
Morphological Approach between the child and the Parent:
Every trait is transferred from parents to children. Each parent contributes equally in the formation of zygote. So it is normal that the child represent the characters similar to its biological parents. The dominant characters are expressed in phenotypically. The child resembles his or her parents many times in features like figure, skin color, nose form, eyes, stature, hair and other personal details. Many a times some deformaties or developmental details are also seen in the child. Many diseases are transformed from father to boy as Y chromosome in inherited from father to son and many diseases are carried from mother to son as X chromosome is transferred from mother to son. In case of female child one X chromosome is transferred from mother to child and another X chromosome from father to child. In female child many times genotype is not represented phenotypically i.e., morphologically as because they are the carrier. Sometimes child represents the trait that their grandparents have, as traits are inherited and transferred from one generation to another.
For example: Hypertrichosis pinnae auris is a Y-linked autosomal dominant trait in which the helix of the ear shows hair growth. This trait is transformed from father to son as it is located on the Y chromosome
Serological Approach
Although blood group studies cannot be used to prove paternity, they can provide unequivocal evidence that a male is not the father of a particular child. Since the red cell antigens are inherited as dominant traits, a child cannot have a blood group antigen that is not present in one or both parents. For example, if the child in question belongs to group A and both the mother and the putative father are group O, the man is excluded from paternity. The table shows the phenotypes (observed characters) of the offspring that can and cannot be produced in the matings on the ABO system, considering only the three alleles (alternative genes) A, B, and O.
| matings | possible children | impossible children |
|---|---|---|
| O × O | O | A, B, AB |
| O × A | O, A | B, AB |
| O × B | O, B | A, AB |
| O × AB | A, B | O, AB |
| A × A | O, A | B, AB |
| A × B | O, A, B, AB | |
| A × AB | A, B, AB | O |
| B × B | O, B | A, AB |
| B × AB | A, B, AB | O |
| AB × AB | A, B, AB | O |
MN blood group also helps in determining blood group: the MN blood group is controlled by autosomal loci which are present in the chromosome 4 and two alleles responsible for this blood group MN are LM and LN. This blood group is determined by the presence of glycoprotein on the surface of the red blood cell. The three phenotypes which are possible are MM, NN and MN. This is also inherited from one generation to another so it helps in determining the paternity. If the mother has blood group M, then the genotype is MM and the child has blood group MN then the father should have blood group N and the genotype is NN. if the mother has blood group M, then the genotype is MM and the child is of blood group M, genotype is MM then the blood group of the father of the child is also M or MN. if the blood group of the mother is N and the child also have the blood group N then the blood group of the father is also N or MN.
Rh System : Rh- child should have both parents Rh- , if one parent is Rh+ then illegitimate child
Immunological Approach through Human Leucocyte Antigen Typing
The HLA test is a test that detects antigens on white blood cells. There are four types of HLAs: HLA-A, HLA-B, HLA-C, and HLA-D. The HLA test provides evidence of tissue compatibility typing of tissue recipients and donors. It is also an aid in genetic counseling and in paternity testing. HLA is a substance that is located on the surface of white blood cells. This substance plays an important role in the body’s immune response. Because the HLAs are essential to immunity identification aids in determination of the degree of tissue compatibility between transplant recipients and donors. Testing is done to diminish the likelihood of rejection after transplant, and to avoid graft-versus-host disease (GVHD) following major organ or bone marrow transplantation. It should be noted that risk of GVHD exists even when the donor and recipient share major antigens. It was recently discovered that a mismatch of HA-1 (a minor antigen) was a cause of GVHD in bone marrow grafts from otherwise HLA-identical donors. HLA can aid in paternity exclusion testing. To resolve cases of disputed paternity, a man who demonstrates a phenotype (two haplotypes: one from the father and one from the mother) with no haplotype or antigen pair identical to one of the child’s is excluded as the father. Conversely, a man who has one haplotype identical to one of the child’s may be the father (the probability varies with the appearance of that particular haplotype in the population). The HLA testing in paternity determination is to identify specific leukocyte antigens, HLA-A, HLA-B, HLA-C and HLA-D (Schonemann, 1998).
Case 1. For HLA: The New York court generally accepted the HLA for paternity dispute solving in the case of Goodrich V. Norman. Court held that alleged father has right to not exclude from the HLA red cells antigen test. Judge of the court found HLA techniques are widely accepted by the scientist. It proved that organ transplant is used to match the donor and recipients. It’s very important when dealing with the lives of the patients.
Case 2. For HLA: In New Jersey Malvasi vs. Malvasi case. Court granted the putative father motions to oblige mother to have HLA testing. Because HLA testing was highly recognised by the scientific community.
DNA Typing
DNA is the deoxyribonucleic acid which is the genetic material and inherited from both the parents. DNA is the ideal source for identification as it is unique in every individual, it shows the blue print. It is a method for identification of the individual used in forensic science. It also helps in the parental analysis by taking the allele size for all microsatellite markers. This technique was developed by Alec Jeffreys in 1987. DNA testing is the most advanced form of proving or disproving biological relationships. The testing is based on the analysis of genetic material between two people (for example: a child and alleged father). DNA is every person’s genetic “blueprint”. Half of their DNA is inherited from their mother and half from their father. When the child’s DNA is compared to an alleged parent and no match exists, that person is excluded 100% as the biological parent. If there is a match in the DNA patterns, a probability of 99% or greater is calculated thus establishing a biological relationship (Klein, 2005). DNA parentage testing is the most reliable and powerful method of proving or disproving parentage – for legal, personal, or medical reasons
Techniques which are involved are:
- a. Variable Number Tandem Repeats (VNTR) : These are short tandem sequences of 10-100 base pairs which are repeated. These regions vary from individual to individual in numbers. Each variant act as an inherited allele allowing them to use as personal identification and parental identification. It is almost impossible having equal VNTR regions in two unrelated person.
Multilocus DNA fingerprinting is one of the important tools in determining paternity because they provide great information, somatic stability and Mendelian inheritance. - b. Short Tandem Repeats (STR): These are short arrays of tandem repeated sequences of 2-6 base pairs in length. These are the polymorphic regions which vary from individual to individual. These are widely used in forensics since 1993. STR is dependent on the PCR which confers much greater sensitivity on the test system. This technique does not consume much time and is used in forensic case work. Greater sensitivity allows the use of more convenient sample. The relative reduction in discriminating power with respect to SLP profiling has a more profound effect in parentage testing, where generally only one allele at each locus is informative, than in identity testing, where a match at both alleles is required. This distinction means that a six locus STR system such as the Second Generation Multiplex (SGM) has been designed which has an equivalent discriminating power in identity cases to four SLPs but many more STRs are required to provide equivalent paternity indices to the six SLPs currently used by the UDL laboratory in cases of disputed paternity (Thomson, 1999).
- c. Polymerase Chain Reaction : It was discovered by Kary Mulluis in 1983. It was established as a standard method for paternity testing. PCR helps in multiplication of a specific region of DNA strand many times. It is the most accurate and fastest method for determining paternity as DNA is inherited from parents to the child. Through PCR one can determine the closeness between two individual or how closely they both are related with each other. The two DNA source is multiplied and seen whether one is derived from the other or if the two had similar parentage. A child inherits a unique combination of DNA from its parents. Because scientists have extensively used PCR for DNA testing, a greater amount of information has been accumulated to form a database for accurate DNA analysis. This large database enables paternity testing via PCR to have the highest power of exclusion (Khanagwal, 2012). According to Chakraborty three human microsatellites which are commonly typed by PCR are apoB, D17S5 which are also known as D17S30 and D1S80. These markers can amplify easily and detected after electrophoresis. Earlier restriction fragment length polymerase (RFLP) is used in determining paternity but nowadays it is not used much as it requires large amount of DNA and takes a long time to process. Now new methods like PCR are used.
DNA Paternity Testing Issues
- Privacy: The person who wants to take the paternity testing can remain anonymous if he/she wants. A test number is assigned that corresponds with a reference number on the kit.
- Reliability: The report of the paternity testing results can be easy to understand by a non-scientist
- Admissible in a court of law
- Social attitudes
Case of Paternity dispute from Hyderabad: the husband’s plea is that he had no access to the wife when the child was begotten can be proved by the DNA test report and in the face of it, court was not able to decide the fatherhood of a child. Then court decided to send them for the DNA test for scientific results. When the scientific reports proved to the contrary and further the innocent child may not be bastardized as the burden is on the mother to prove that the revision petitioner is the father, from the marriage also in dispute, equally of any conjugal life.” While dismissing the revision petition, justice Siva Sankara Rao ruled that the DNA test helps as a solid proof on truth of the dispute of paternity.
N.D Tiwari Case