P-TEST - system of anonymous paternity testing in GENERI BIOTECH

• About DNA paternity tests
  • General information
  • Principles of DNA tests
  • Probability calculations
  • Comparison of DNA tests
• Anonymous vs. expert tests
  • Anonymous tests

Principles of DNA tests

DNA tests are performed by means of molecular biological methods that use hi-tech molecular technologies. Based on the same principles, DNA tests are used also in criminal science. In DNA tests, the matching of selected polymorphic markers is investigated in the DNA sequences of the tested persons. Microsatellite regions of DNA are mostly used as polymorphic markers that are highly polymorphic, and ensure a high degree of accuacy of the result. The most commonly used microsatellite regions are STR (short tandem repeats) polymorphisms or VNTR (variable number tandem repeats) polymorphisms. Both types of polymorphisms differ by their length of repeating sequence: STRs have a repeating motif 2-5 nucleotides long whereas VNTRs have many tens of nucleotides. The number of motif repetitions depends on the type of polymorphism.

Taking a sample for DNA testing is performed by rubbing the mucous membrane of the mouth with a brush that has fine bristles. After taking sample, the bristles contain cells that are liberated normally by the mucous membrane to the saliva. Although it seems at first glance that the brush is clean, it does contain cells whose DNA can be isolated in the lab. See detailed info on taking sample.

DNA (deoxyribonucleic acid) as a material basis of inheritance is totally specific for each human. Features that are comprised in DNA are inherited from parents to their children. After isolation of DNA, it is used in a polymerase chain reaction (PCR). After PCR, it is possible to compare polymorphic areas of a tested child and an alleged father. In GENERI BIOTECH we provide analysis of 16 polymorphisms to achieve reliable results.