Saturday, May 3, 2008

DNA Paternity Tests: What Are They?

DNA paternity tests are used to determine if a man is in fact the biological father of a child and are done to either determine or to rule out paternity. These tests can even be done before the baby is born if necessary, although there may be a slight risk to the fetus, so in most instances, it is recommended and preferred to wait until after birth for testing. Postnatal paternity tests pose absolutely no risk at all to the infant and can be conducted at any time after birth.
Photo:  renjith krishnan

DNA Paternity Tests Explained

Deoxyribonucleic acid, or DNA as it is most commonly referred to as, is an extremely vital molecule that is found in every living thing on earth. DNA contains the basis of our heredity and dictates which particular traits are passed on from one generation to the next.

Human DNA resembles a tightly coiled double helix, or more simply, a twisted ladder. The two sides of the ladder are comprised of four bases and the "rungs" are hydrogen bonds which connect the bases to one another. The way the molecules are arranged is referred to as the DNA sequence, which in essence, is a detailed list of instructions that dictate the specifics of physical characteristics found within our genes.

For testing purposes, chemical agents are used to extract the DNA from the samples collected and a profile is created using a complex process that detects what are known as loci, or locations, on the DNA helix. The testing continues as each loci is detected through a molecular replicating process that is used to create a "map" of the DNA's loci which is referred to as the DNA profile.

If half of the loci from the child's sample are found to match those from the alleged father, paternity is established and he is determined to be the biological father. If three or more loci do not match those from the alleged father's sample, he is excluded from paternity. Depending on the specific markers that don't match the child's, further testing may be done to ensure that the results are conclusive and completely accurate.
Photo:  jscreationzs

Different Types of DNA Paternity Tests

There are two methods commonly used to collect DNA samples for postnatal paternity testing. Also referred to as a "cheek swab," the buccal sample collection method is completely painless and involves swabbing the inside of the cheek with a large cotton swab that contains special fibers which allows the DNA to adhere to it.

                                  Photo:  Boston Paternity

The "pin prick" method involves a small lancet that's used to prick the finger to collect a small amount of blood that's transferred to a collection card, which is then used to test the DNA. It's usually recommended that children under the age of 8 have their blood samples collected by a qualified physician, or to simply use the buccal swab method instead.
                                        Photo:  BBC News

It is even possible for paternity to be established using the DNA of the alleged father's parents if he is missing, deceased, or otherwise unavailable for testing. In this instance, samples from both of the man's parents will then need to be collected and tested.

Wednesday, April 30, 2008

An Overview of the Home Paternity Test

Thanks to many advances in modern science, it's now possible to determine, or rule out, matters of paternity through the convenient use of a home paternity test. In-home paternity test kits are now available for purchase for a relatively low fee, usually $30 or less, in which the samples are collected in the privacy of one's home, and then returned to the laboratory for testing. An extra fee will apply for the lab to conduct the actual DNA testing, and results are usually returned within a week's time.

With a home paternity test, DNA samples may be collected using one of two methods; either the buccal (cheek) swab, or a blood test. The former is completely painless and able to be done on people of any age, involving a long cotton swab that's swirled inside the cheek to collect cells for testing. The blood test involves a small lancet used to prick the finger, dropping the blood sample onto a collection card and mailing back to the lab for processing.

Results will be returned in a discreet mailer generally within five business days, although expedited service is usually available for an additional fee.
Photo:   DNASolutions

Legal Issues

The Chain of Custody refers to an exact process that must be followed in order for DNA test results to legally be admissible in court. Much like evidence from a crime scene, the results of the paternity test must be handled according to specific procedure which begins with the collection of the samples, and also includes their transmission back to the laboratory as well as the complete testing procedures that are done. If you will need the results of your test for legal purposes, always deal with a laboratory or company that offers legal testing following the Chain of Custody process.

Here are some of the most frequently asked questions about home paternity testing:

Q: What if the alleged father is deceased or missing, can paternity still be established?

A: Yes, if any viable samples are available, such as blood, hair, tissue, or body fluids, they may be used to determine paternity. If this also isn't a possibility, both of the man's parents may then be tested to establish whether or not their son is the father of the child in question.

Q: Are there any age limits associated with paternity tests?

A: No, paternity tests can be done at any age, at any time, and even be conducted before a child is born using prenatal paternity testing procedures, although these both pose a certain amount of risk to the fetus and mother and should be discussed thoroughly with a doctor. The postnatal buccal swab method is completely safe and is able to be done on newborn infants.

Q: What is DNA banking?

A: Some laboratories associated with home paternity tests offer a service known as DNA banking which allows you to keep your DNA samples in their records in the event it is ever need in the future. DNA banking is optional, not available through every company, and the fees will vary from one lab to the next.

Q: Is it possible to alter or "fake" the results of a home paternity test?

A: The DNA within our cells is there from the moment of conception. When an egg and sperm combine to create what will eventually become the fetus, the genetic markers are already in place and cannot ever be changed or altered.

Q: Does testing have to be completed on each person at the same exact time?

A: No, testing can be done at different times provided each of the samples are handled correctly and then stored properly.
Photo:   djcodrin

An Overview of a Paternity Test Kit

A paternity test kit, often referred to as an in-home paternity test kit, brings the complex world of DNA testing right to your home without the need for any specialized knowledge on your part. As of only recently has it become possible to purchase a paternity test kit without the need for spending a fortune going through a private laboratory. In fact, a home paternity test kit can now be bought right over-the-counter at drug stores in many locations throughout the U.S. for as low as $19.99, although the lab's processing fees will be an extra charge.

Here is an overview of a basic paternity test kit and the different steps involved with the process:

After ordering your paternity test it should arrive in a discreetly marked package for your privacy, including an equally plain return envelope or package for mailing the completed test kit back. While the specifics may vary from one company to the next, basically, the first step is accurately labeling the collection envelopes and filling out all of the required information, then collecting the samples as directed, and simply mailing them back to the laboratory.

1. Step One: Each person being tested will have a separate envelope to hold their individual samples for mailing. The envelopes, or mailers, are also where necessary information is to be listed, including the person's race which is needed to calculate statistical data related to DNA.

2. Step Two: Most kits provide a total of four specially treated cotton swabs, two for the inside of the left cheek, and the other two for the right, for each person. When removing the swabs from their plastic wrapping, open at the opposite end of the cotton tip taking extra care not to touch the tip to the outside of the package or any other surface.

Each swab should be rubbed against the inside of the cheek, rotating and swirling the tip briskly without rubbing it on the same area over and over again. Combining a back and forth and up and down motion tends to work best. After using one swab, immediately put it into the collection envelope, sealing after both swabs are used. The swabs should NOT be placed back into the plastic sleeves as this will promote the growth of mold, which could actually destroy the DNA.

3. Step Three: After all three people have been tested using all four swabs that are now in sealed envelopes, complete and sign the form or forms included that indicate how you will be paying for the testing, and how you wish to receive your results. Some laboratories also offer the convenience of retrieving DNA paternity results online via a web site or email in addition to receiving them by regular mail.

The completed kit, including the individual, fully labeled envelopes and any consent forms are then placed inside one larger mailer, usually postage-paid, and sent back to the laboratory for processing. Generally, results are available for delivery within five working days after the test samples are received at the lab via first-class mail, telephone, or email, and expedited service may also be available for an additional fee.

DNA paternity test results will be able to tell with 100% certainty if a man is not the father, and offer a probability of at least 99.9999% if he is the biological father of the child tested.
Photos courtesy of  JenaGen