Category Archives: dna test
I have hair for one of the people I want tested. I notice on TV that they use this all of the time. Can I use this? How about baby teeth? Would these stand up in court?
Unfortunately, hair often isn’t as good of a sample as television makes it look. On TV, you often see a crime investigator discover a single hair, and within moments they not only have a full DNA profile, but they know exactly who it came from. The truth is that technology simply isn’t there yet, though it could be someday.
In order for us to use hair, we need the hair roots. This is because there simply isn’t adequate DNA in the hair shaft. For us to have enough DNA to attempt the type of profile we need for a paternity test, we would need at least 12 hairs with the root bulb. This means that pulled hair is what we need. Typically, hair off of a hair brush is broken hair that doesn’t contain the root.
We often get asked about teeth or baby teeth as well. The main source of DNA in a tooth is the pulp, and the pulp usually doesn’t survive longer than one year after it has been extracted from the mouth. If there are bits of dried blood still on the tooth, we can attempt a profile from the blood but there is still no guarantee we will yield a profile.
Often times, when people are interested in using hair or baby teeth, it is because they do not want that testing party to know about the test. If secrecy is what you are after, there are other types of samples you can use that would give us a better chance of yielding a profile. Some examples of samples where we generally have a good chance at yielding a profile include: Toothbrush, Q-tips used on ears, electric razor clippings (for the skin cells in them), chewing gum, cigarette butts, soda straws, Kleenex or a clothing item with blood on it.
Other options you have, but don’t have as good of a chance at yielding a profile may include: Licked envelopes or stamps, the rim of glasses or bottles, tissue slides, fingernail or toenail clippings, and dried umbilical cords.
Any time you use a non standard sample (any sample that is not a buccal swab, tube of blood, or blood stain card) there is a fee for us to attempt a profile. This fee varies on the type of sample being sent, but generally ranges between $200 (most of the aforementioned options are $200) and $1200 (bone or teeth). In the event a profile is unsuccessful, the fee is non-refundable. Maintaining the chosen sample in a cool, dry area will maximize our chance of getting a profile. Keeping the sample in a paper envelope is better than keeping it in a zip lock bag.
It is important that only the intended person have used the artifact in question and no one else. It is also important that when handling the sample, you do not touch the part that needs to be tested. This is because if the sample yields a mixed profile (we discover more than one person’s DNA profile), the sample may not be used.
One last thing to keep in mind is that any time a sample is not collected with a legal chain of custody, that sample cannot be used for court or any other official purpose (social security, birth certificate, custody, child support, etc.) When a sample is collected with a legal chain of custody, the testing parties to a location where photo identification is checked, a photo is taken, and the collection is conducted at that time by a non-biased third party. Since hair, toothbrushes, and similar samples are typically just items taken from around the home, there is no way for us to verify the identity of the person that the sample came from, and therefore that test cannot stand up in court or be used for any official purposes. However, if you are simply trying to get a personal question answered, pursuing this route may still be worth it for you.
There are a few different avenues you can explore when an alleged father is deceased or missing.
If the alleged father passed away in the last few years, it is possible that the hospital, pathologist, or medical examiner has maintained a DNA sample. The most common types of sample maintained are blood cards and tubes of blood. If a sample has been maintained, the Next of Kin (usually the child, spouse or parent of deceased) must give permission for the facility to release the sample to our lab for DNA testing or a court order must be obtained. When a DNA sample for the alleged father is available then specimens from the mother and child are obtained and a paternity test can be performed. If a standard sample has been maintained for the alleged father (buccal swab, tube of blood, blood card) the price is the same as a standard paternity test.
If another type of sample exists (pathology slide, paraffin block with tissue, etc.), we can attempt to get a DNA profile from that specimen. In some rare cases, a body can be exhumed and a bone sample can be used. However, an unusual specimen fee would apply for any sample that is not a buccal swab, blood card, or tube of blood, and that cost depends on the type of sample to be tested. There is no guaranty that DNA will be obtained from a DNA profile from an unusual sample, and the specimen fee is nonrefundable in the event we are unsuccessful. The unusual specimen fee also does not include the cost of any paternity or relationship analysis. To discuss the price of an unusual specimen and to discuss the likelihood of getting a profile from that specimen, it is usually best to call and speak with one of our representatives.
If a sample has not been maintained on the alleged father, another option is a grandparent study. In a grandparent study, we need both of the alleged father’s biological parents, the child, and his/her mother. In a grandparent study with the child’s mother, we can still guaranty a 99.99% probability of paternity on a positive test, but on a grandparent study without the child’s mother we can only guaranty a 99% probability. This is because everyone gets half of their DNA from their biological mother and half from their biological father. When we have the child’s mother’s DNA, we eliminate what she gave to the child, and we only compare the other half of the DNA against the grandparents. This is also the reason both grandparents’ DNA is necessary. Between both biological grandparents, we have the alleged father’s DNA profile. If only one of the alleged father’s parents is tested, then only half of his profile is available, and a conclusive result cannot be guaranteed.
In the absence of an available sample for the alleged father and if both of his parents are unavailable, another possibility is a family reconstruction. This is where DNA profiles of surviving relatives of the alleged father are compared to the DNA profiles of the child. We prefer to have the child, the child’s mother (to eliminate what she gave to the child so we know exactly what the child inherited from his/her biological father), and three direct relatives of the alleged father (parent, full siblings, known children). We encourage at least 3 direct relatives, and it is the same price whether one direct relative or all 3 participate (with the exception for the specimen fees). The more surviving direct relatives of the alleged father that participate in the test, the better chance there is of obtaining a conclusive answer. The reason this type of test is a last resort is that it is expensive, it can take much longer, and we cannot guaranty a conclusive answer.
If the child is male and the alleged father has a full brother (who shares the same father), known son, or father who is still living, a Y chromosome study may be available. This only indicates whether or not the testing parties share the same male lineage. It does not indicate the relationships of the testing parties, and does not determine that the alleged father is the father of the child.
If the test does not need to be used for anything official and you are just trying to answer a personal question, you may be able to pursue a home test. This is where an artifact maintained from the alleged father (licked envelope, tooth brush, etc.) is used as his sample and buccal swabs are used for the child and mother. As stated above, any sample that is not a buccal swab, blood card, or tube of blood is subject to an unusual specimen fee, and this fee would apply for the artifact used for the alleged father’s specimen. Since we cannot verify the source of the artifact sample (i.e., we cannot prove whose DNA is on those samples), this test cannot be used for anything official and will not stand up in court.
A few times we have had customers ask if they can use a print-out of the alleged father’s DNA profile from a previous test to compare to the child. If there is a proper chain of custody and permission from the next of kin then it may be possible to use those results for a legal paternity test, but there is no way to be sure. If results don’t need to be used for anything official then using an old profile for comparison is usually possible. However, this route does pose a few limitations. Firstly, we only have the DNA loci on the print-out available for the alleged father’s profile. In other words, if we compare those locations to the profile of the child, and additional testing is needed to get a conclusive answer (either 4 mismatches on a negative test or a 99.99% probability on a positive test), we would not be able to complete the additional testing since all we have is a print-out of the alleged father’s profile instead of having the sample to run more DNA locations.
Also, on all negative tests, the AABB (the accrediting body for relationship testing laboratories) requires the samples to be run twice to rule out the possibility of a sample switch or contamination in the laboratory. We cannot verify that the sample was run a second time on the original test with the alleged father’s profile on it.
Is there a non-invasive prenatal paternity test that meets PTC’s high standards of quality and reliability?
There is a new baby coming. The problem is that there are two possible fathers! Until recently it was impossible to reliably determine paternity before birth without an invasive and risky procedure.
For several years it has been possible to have a paternity test from the mother’s blood, but the results were very often incorrect. There was really no point in having the non-invasive test because it was so inaccurate that the chance of obtaining a correct answer was just about the same as the chance of receiving a wrong answer.
That has changed. New technologies and methods for isolating the fetal DNA from the mother’s blood have made it possible to reliably determine paternity before birth without the risks and cost associated with invasive procedures such as amniocentesis and Chorionic Villus Sampling (CVS).
Paternity Testing Corporation has been the leader in reliability of DNA testing for more than 15 years. The most important aspect of DNA paternity testing is ensuring the parents that the answer obtained is the correct answer. In more than 15 years of paternity testing we have NO instances where the results of a PTC paternity test have later been shown to be incorrect. As far as we know, each and every test that we have issued has the correct paternity determination. PTC is the only large paternity laboratory that can make this statement.
Making sure that each and every paternity test is correct is not a matter of luck or coincidence. Only being very careful, having protocols in place that are followed exactly for each case, and continually checking for consistency will result in correct answers each and every time.
Before PTC offered this new non-invasive prenatal paternity test we performed a great deal of research. We knew that many of the non-invasive paternity tests previously offered were inaccurate. We had seen several examples of inaccurate tests first hand. Parents questioning the results of a non-invasive prenatal test came to us for help. In 13 instances (far more than half of the cases we have seen) the results of the non-invasive tests were incorrect. A non-invasive prenatal test is very difficult. The test is only accurate if performed correctly and carefully each time. In order to ensure accuracy of the test, the testing procedure must be repeated and produce identical results. The statistical calculations must be sufficient to ensure an acceptable level of reliability. Everything must be perfect each time.
Only one fetal DNA laboratory is capable of meeting the high standards of PTC. This laboratory has been performing these tests on a very limited basis for 4 years. Until recently, the lab only performed this testing for criminal cases. Performing the tests accurately takes time, patience and a great deal of skill. The testing is very labor intensive and requires analysts that are proficient in fetal DNA isolation techniques. This laboratory focuses on non-invasive prenatal testing for genetic disorders and, until recently, could not commit sufficient staff and time to perform larger numbers of paternity tests.
PTC is now able to offer this test to the general public. We are proud to announce that we are working in conjunction with our affiliate laboratory to bring this reliable non-invasive prenatal test to every family in need.
Knowing the answer before the baby is born is incredibly important to many families. The family begins bonding to the baby long before birth. Waiting until birth in order to determine the father of the child not only impacts the mother and her family but also changes the lives of the potential father(s) and their families. Everyone is anxious and hesitant to move forward until the answer is known.
If you are in need of a non-invasive prenatal paternity test please contact PTC. You may contact PTC by email or by phone: firstname.lastname@example.org or 888-837-8323