http://en.wikipedia.org/wiki/Paternity_fraud
Paternity fraud
Paternity fraud is the term introduced by fathers' and men's rights activists for paternal discrepancy or a non-paternity event, in which a mother names a man to be the biological father of a child, particularly for the purpose of collecting child support (also referred to as child maintenance), when she knows or suspects that he is not the biological father.
http://en.wikipedia.org/wiki/Parental_testing
Parental testing
Parental testing is the use of genetic fingerprinting to determine whether two individuals have a biological parent-child relationship. A paternity test establishes genetic proof whether a man is the biological father of an individual, and a maternity test establishes whether a woman is the biological mother of an individual. Though genetic testing is the most reliable standard, older methods also exist including ABO blood group typing, analysis of various other proteins and enzymes, or using human leukocyte antigen antigens. The current techniques for paternal testing are using polymerase chain reaction (PCR) and restriction fragment length polymorphism.
DNA testing is currently the most advanced and accurate technology to determine parentage. In a DNA parentage test, the probability of parentage is 0% when the alleged parent is not biologically related to the child and the probability of paternity typically greater than 99.9% when the alleged parent is biologically related to the child.
The U.S. Department of State and USCIS provide information concerning the DNA parentage test request for immigration purposes.
http://dictionary.reference.com/browse/zero
zero
having no measurable quantity or magnitude; not any
