© Comprehensive Genetic Services, SC

INFORMATION ABOUT PATERNITY TESTING

Paternity testing is a personal matter and we make every effort to maintain the confidential nature of the testing. The wait for paternity test results may be an anxious time. We hope the following information will provide answers to your questions and help alleviate some of your concerns. If you have additional questions that are not addressed here, please call us at CompGene.

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  • What is the process of a paternity test?

  • How long will it take to get my results?

  • How much does paternity testing cost?

  • Must my account be paid in full to receive results?

  • How old must the child be for paternity testing?

  • Do the mother and the alleged father(s) have to come in together for the testing?

  • Do mouth brushings yield as accurate a result as a blood sample?

  • Is the "chain of custody" procedure necessary?

  • How is DNA analysed for a paternity test?

  • What results will I get from a paternity test?

  • What does a negative paternity result (exclusion) mean?

  • What does a positive paternity result (inclusion) mean?

  • How Will I Be Notified of My Results?

  • May I Call For Information On My Test?

  • Example Cases

  • Legal Considerations

    What is the process of a paternity test?

    All participating adults will be required to fill out paperwork consenting to the paternity test. DNA samples are taken from the mother, the child(ren) and the alleged father(s). DNA can be obtained from any body tissue but typically blood or brushings from inside the mouth are used. These samples are obtained and handled following "chain of custody" procedures. These are steps to ensure that a particular DNA sample is from a certain individual. A photograph or fingerprint is taken at the time of blood drawing or mouth brushing and a photocopy is made of a person's driver's license or social security card. Typically, a photograph is taken of the mother and her child and a second photograph is taken of the alleged father. The photographs are signed and dated by the photographed individuals.

    How Long Will It Take to Get My Results?

    CompGene usually provides reports within 7-10 days. Some testing situations may take a little longer, such as when autopsy specimens or archival pathology samples from deceased individuals are used or tissue culture is required.

    How much does paternity testing cost?

    The standard fee is $325 (mother,child and alleged father). Mother deficient cases are charged at the standard trio rate. A rush completion of paternity testing (3 working days or less) is available but carries a $300 additional fee paid in advance.

    Must My Account Be Paid in Full To Receive Results?

    A $150 non-refundable deposit (included in the $325 fee) is required upon receipt of the first sample before testing will begin. Results will be released promptly upon full payment. Payment in the form of cash, check, money order, debit card or credit card. Paying in full prior to test completion will expedite the release of test results.

    How old must the child be for paternity testing?

    Unlike the older paternity testing methods which require infants to be at least six months old, DNA based paternity testing can be accurately performed at any age. It can even be done before birth on amniotic fluid cells or chorionic villi. Cord blood obtained at delivery can also be used.

    Do the mother and the alleged father(s) have to come in together for the testing?

    Individuals being tested do not have to come in at the same time to have DNA samples obtained for paternity testing. DNA can be safely stored for many months until analyzed. In our experience, we have found that people often feel more trusting of paternity test results if they have witnessed DNA samples being obtained from each other.

    Do mouth brushings yield as accurate a result as a blood sample?

    The results from mouth brushings are just as accurate as results from blood. However, if the mouth brushing is not performed vigorously, the amount of DNA obtained may be insufficient and a rare test failure may occur. In this situation, a repeat sample is obtained and the test is repeated at no additional charge.

    Is the "chain of custody" procedure necessary?

    If "chain of custody" procedure is followed the paternity testing results will withstand most conceivable legal challenges. The "chain of custody" procedure does not have to be followed, but if it is not, the highly accurate paternity test results may not stand up in a court challenge.

    What if one individual(s) to be tested lives in another city or state?

    CompGene will priority ship mouth brushing DNA collection kits to individuals who do not live locally. A shipping fee is added to the initial deposit for testing.

    How is DNA analysed for a paternity test?

    All DNA samples will be analyzed with a widely used patented procedure called the polymerase chain reaction (PCR). The PCR is a very sensitive and accurate method to analyze DNA. The paternity test will reveal the true relationship of the alleged father to the child for the following reason: a child receives half of his (her) DNA from his (her) biological mother and half from his (her) biological father. Therefore, the rationale behind paternity testing is to determine whether or not a child has DNA in common with his (her) alleged father. A child who has DNA that is not found in his (her) biological mother and is not found in his (her) alleged father cannot be the child of that man. Unless otherwise indicated, maternity is always assumed to be as stated.

    What results will I get from a paternity test?

    A paternity test report will state the technical name for each DNA area that has been tested. Paternity testing at CompGene typically evaluates at least 9 different areas in the DNA. You will receive one of two possible results of your paternity test. The report will either be a 1) negative paternity result (exclusion) which means the alleged father is not the biological father or a 2) positive paternity result (inclusion) which means the alleged father has greater than a 99.99% chance of being the biological father. The reasons for either of these results are explained below.

    What does a negative paternity result (exclusion) mean?

    Non-paternity occurs when a child is found to have DNA that is not in his (her) alleged father and is not found in his (her) mother. If this occurs, the alleged father CANNOT be the biological father of the child. This result proves non-paternity without a doubt. There are two important points to understand about a report of non-paternity.

    First, when we provide a report of non-paternity it will show at least 3 areas of DNA that do not match between the child and the alleged father. The reason for requiring at least 3 non-matching DNA areas is that it is possible that a child might have a change in the DNA (a mutation) he (she) inherited from his (her) biological father. This would make it appear that the child is unrelated to his (her) true father. By requiring at least 3 non-matching DNA areas, the chance of a false non-paternity report due to a naturally occurring mutation is virtually impossible, barring laboratory error.

    Second, on a report of non-paternity, some DNA areas tested will match between the child and the alleged father. This occurs because all people share some common DNA areas. However, when several DNA areas are compared, non-related individuals will always have some areas that do not match. As explained above, the presence of 3 or more non-matching areas on the paternity test report is proof of non-paternity.

    What does a positive paternity result (inclusion) mean?

    At each DNA area are a number of different possible DNA patterns (called alleles). Different people have different alleles. The report will state for each DNA area tested which allele the alleged father and the child share and how common that allele is in the alleged father's ethnic group. When every DNA area tested shows a shared allele between the alleged father and the child, there is a very high chance that the alleged father is the biological father. It is important to appreciate that although a negative paternity result (exclusion) provides absolute exclusion of an alleged father being the biological father, a positive paternity result (inclusion) only provides a high statistical probability that the alleged father is indeed the biological father. All testing at CompGene will provide (except in rare circumstances) a probability of paternity of at least greater than 99.99%. This figure yields a paternity index of > 10,000. This means that there is less than a 1 in 10,000 chance that the alleged father, deemed the biological father by paternity testing, is actually not the biological father. Most courts require a 99% or higher probability of paternity (a paternity index of > 100).

    How Will I Be Notified of My Results?

    Test results can be picked up in person or mailed to all tested adults and any representative they have requested on their identification forms. Results can be faxed to a designated medical or legal representative if requested by an authorized individual. No results will ever be given over the phone.

    May I Call For Information On My Test?

    Yes. However, the only information we will be able to provide is whether or not your testing has been initiated and or has been completed. As a matter of policy, CompGene representatives who answer the telephone do not have any information about the results of paternity testing. This policy prevents them from inadvertently revealing any confidential information. Only the laboratory personnel actually performing the paternity test know the results and will never give results of a paternity test over the telephone.

    Paternity testing takes time, and we can only determine the results of the test after completion of all aspects of the testing. We will notify you when the test is complete. Unless you hear from us, assume your test is proceeding properly. If you call, please be ready to provide the same identification information that you presented at the time of blood sample collection.

    Example Cases

    The two cases illustrated below show DNA data that either support the statement that the alleged father is not the biological father (exclusion - panel A) or support the statement that the alleged father is the biological father (inclusion - panel B).

    In case A, an autoradiograph shows a DNA area from the mother, the child and the alleged father, respectively. In the middle lane, the upper DNA area seen in the child is not found either in the mother or in the alleged father. It must have come from another man, the biological father. These results are consistent with exclusion. The alleged father is not the biological father.

    EXCLUSION

    Mother Child Father?

    In case B, an autoradiograph shows a DNA area from the mother, the child and the alleged father, respectively. In the middle lane, the child's upper DNA area comes from the mother while the child's lower DNA area comes from the alleged father. These results are consistent with inclusion.

    INCLUSION

    Mother Child Father?

    Although these examples show only one DNA area, typically a paternity test evaluates at least nine different DNA areas. Multiple DNA areas are studied to exclude the possibility of false positive or false negative results.

    Legal Considerations

    No paternity testing is performed at CompGene unless all participating adults are aware that they are being tested. All participating adults will be required to fill out paperwork consenting to the paternity test. In case your paternity test results are needed for a legal proceeding, CompGene will always have your file available and will release results only with your written consent. A qualified molecular geneticist is available on an hourly basis to testify as an expert witness if your legal proceedings require it.