Posted on
02 March 2010, under
Health; More Health articles...
DNA Lab Test
Paternity DNA testing is a relationship test that specifically seeks to establish whether an alleged father is the true biological father of a child. Paternity testing is the most accurate test available for determining this type of relationship and relies on the comparison of the persons’ genetic profiles to determine if they share similar DNA or not. Following the development and adoption of this test, other methods previously used, such as blood group typing, have stopped being used as they do not offer the same level of conclusiveness.
Can A Paternity Test Be Done Without The Mother’s Samples?
Yes, a paternity DNA test can be done without the mother’s samples; such a paternity test is referred to as a motherless paternity test. Ideally, a paternity test is done with the mother’s samples; however, motherless paternity tests are common and just as reliable. A paternity test done without the mother’s DNA samples will usually still provide an inclusion rate of 99.9%; the exclusion rate will be of 100% should the tested father not be the child’s biological dad. Including the mother’s samples can strengthen the result and give a probability in excess of 99.999%.
How Is A Paternity DNA Test Done?
Paternity tests are usually done using oral mouth swabs to perform the DNA sampling. The swabs look very much like cotton buds but are of course, sterile. These cotton tipped applicators are rubbed on the inside of the mouth, under the tongue and the inner cheeks so as to collect saliva. Although the sample is referred to as a saliva sample, it is the cheek cells collected by the swab during rubbing that are necessary for testing. The advantages of oral swabs are that they are non-invasive and cause no discomfort to the individual involved, unlike for example, medical blood draws.
When Will I Need An ‘At-Home’ Paternity Test And When A Legal Paternity Test?
‘At-home’ paternity DNA tests are sometimes called ‘peace of mind’ tests and are done when one simply wants to resolve a doubt regarding paternity in a quick and straightforward manner. Many DNA testing companies send out ‘home DNA testing’ kits which allow clients to collect their own DNA samples in the privacy of their own home. Once they have collected their samples, these will be sent back for testing at the laboratory. ‘At-home’ tests have no legal standing because the identity of the donors of the samples cannot be verified and therefore doubts may be raised regarding to whom the profiles actually belong to. The disadvantage of this test is that there may be deliberate exchange of DNA samples by someone taking part in the test in order to obtain a negative result.
A legal DNA test is normally done when one requires the test for legal or official purposes. To have legal standing the DNA sampling must follow a procedure which is known as a ‘chain of custody’. All samples are collected by a neutral third party, such as a doctor or qualified nurse, who is formally referred to as a ‘Sampler’. Moreover, the chain of custody requires identification and copies of the identification of those taking part in the test. Photos will also need to be provided. The Sampler will need to sign the photos so as to verify that the people taking part in the test are the same individuals in the photos and in the identification provided. Only by adhering to the chain of custody will the results usually be court admissible.
How Is DNA Tested?
Once your DNA samples have been collected they are then sent for testing in the laboratory. The laboratory will extract the DNA from each of the samples provided and this is processed to generate a DNA profile for each. The DNA profile consists of a number of specific regions on the DNA known as genetic markers or ‘loci’. Many laboratories will analyse 16 of these loci, which is the minimum internationally accepted standard for this type of test. An inclusion for paternity will mean that there is a match between all 15 genetic loci on the father’s DNA profile and the child’s (one of the markers is the Amelogenin gene which will confirm the sex of the person tested). If there are loci which do not match, then the tested father will be excluded as the child’s biological father with 100% accuracy.
If I Decide To Do A Test What Should I Look Out For When Ordering?
Once you have decided to proceed with the test you should make sure that the company you order the test from offers testing performed by an ISO 17025 accredited laboratory. This accreditation is one of the most widely accepted accreditation for this type of testing and will provide you with the peace of mind you require regarding the accuracy of your test result. Once you have confirmed this, you can proceed to order the ‘at-home’ test or legal test depending on your requirements. You should also expect to receive the results of the test normally within 5 to 7 working days from when the samples are received at the laboratory.
easyDNA Ireland offers reliable, accurate and cost-effective DNA testing solutions and has been operating in Ireland for over three years through its office in Dublin. For further information visit www.easydna.ie
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