Paternity test frequently asked question
How accurate is DNA testing?
DNA paternity testing is the most accurate method currently available for determining familial relationships. The test will indicate with 100% certainty if the tested male is not the biological father for exclusion of paternity and will demonstrate with greater than 99.9% probability that the tested male is the biological father for inclusion of paternity.
What is the biology behind DNA Forensic testing?
The molecular biology of DNA forensic analysis was first developed by Dr. Alec Jeffreys (now Professor Sir Alec Jeffreys) for a sexual assault case in England. The terms ‘DNA Fingerprinting’ and ‘DNA profiling’ now all refer to the same technique. Dr. Jeffreys discovered that the repeated DNA structures he was studying had the same core sequences: the variation he observed was unique to each individual. When this approach was applied on a slightly larger scale, each individual would have a unique pattern, distinguishable from all others. This forms the basis of current DNA forensic testing.
What are STRs that are used for DNA forensics?
STRs is an acronym for Short Tandem Repeat. These are genetic elements (sequences in the DNA) that are used in forensic DNA analysis. There are other genetic elements that can be used for determining identity, but STRs are considered the the most accurate and reliable method. They are the only markers IFI uses.
Who needs to be tested?
For a typical DNA paternity test, a sample is collected from the mother, child and alleged father. Paternity can also be accurately determined in the absence of the mother, by testing only the child and alleged father. A DNA paternity test can be performed on individuals at any age, even prenatally!
Can you tell something about a person from DNA forensic testing?
Actually no, there is no genetic, health or disease susceptibility information in DNA analysis using STRs. It only provides an STR profile that can be used, in conjunction with a database, to positively identify an individual.
What kind of sample is needed for DNA forensic testing?
The test requires DNA. DNA can be extracted and analyzed from blood, semen, saliva, skin scrapings, hair, bones or teeth. Even minute amounts of material can be sufficient to obtain a DNA profile.
What are the different methods of performing DNA forensic analysis?
To simplify a little, the methods depend on which kind of laboratory instrument is used to obtain the STR profile. All methods use PCR amplification in order to analyze STRs; IFI then uses an industry standard capillary electrophoresis instrument to analyze the results of the amplification.
What is PCR?
PCR is an acronym for Polymerase Chain Reaction. This is the molecular biological technique that can amplify specific regions of DNA with great accuracy. Using this technique sufficient quantity of DNA can be produced in a few hours such that the STR profile can be determined.
What is CODIS?
CODIS is an acronym for Combined DNA Index System. It is a searchable database maintained by the FBI (for further information, go to the CODIS home page that contains more than 1,000,000 DNA profiles.
How long does the test take?
The specimen collection appointment is 15 minutes in duration. Results are available approximately 3 to 5 working days after your appointment.
What is needed?
In most cases, a small blood sample is collected during your appointment. A DNA sample may also be obtained painlessly from the mouth with a cotton swab (buccal swab). You may choose the collection method that you prefer during the time of your appointment. For newborns, DNA paternity test can be performed safely using umbilical blood from the umbilical cord. In unusual circumstances, DNA can even be collected from other sources, such as bone, hair, old blood samples or stains, semen, saliva, or even from a deceased individual.
What if the mother cannot be tested
Paternity can be accurately determined even if the mother is not tested.
What is mitochondrial DNA and how it is used in DNA forensics?
Most DNA forensic work uses genomic DNA: the genetic material within the nucleus of the cell. Mitochondria are organelles (an intracellular compartment) that contain a small, circular genome that can also be used for genetic identification testing. The methods and analysis of mitochondrial DNA are fundamentally different from genomic analysis: sequencevs. allele based, maternally inherited vs. Mendelian. Mitochondrial DNA analysis is used particularly on old or degraded samples where STR analysis is likely to fail.