Author Topic: Help with twins DNA test results...please  (Read 1729 times)

Offline beautycr75

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Help with twins DNA test results...please
« on: Sunday 06 March 11 06:31 GMT (UK) »
Hello,

 I have somewhat of a unique and baffling situation of a genetic nature that I hope you may be able to help me with or possibly direct me to someone who can give me a definitive answer.

My husband and his fraternal twin are in search of their biological father, their mother passed away a few years ago.  We had a paternity test ran on the alleged father and my husband’s twin brother, using a home testing kit from IDENTIGENE.  The test came back inconclusive, because 2 of the 17 alleles tested for did not match; but the alleged father could not be excluded.  The results also stated that the mismatch at one of the alleles could be consistent with a mutational event. Through a friend, I had a professor of Biology at Indiana State University, with some experience in testing such as this, to try to help clarify the results.  She noticed that in the case of the second mismatch that the test showed the child having only one allele. She said that it could mean that the child was homozygous, or that the second allele may never have been detected in the testing, therefore leaving the possibility that the second allele might match the alleged father’s.  She also told us that 15 out of 17 matches was reasonably high and that the test was only inconclusive from a legal standpoint, because legally it took 3 mismatches to exclude a potential father. She told us the alleged father had a 99.9988810967154 % probability of being the biological father. She obtained that number using the following website: http://www3.kmu.ac.jp/legalmed/DNA/stre.html .

Due to the confusion and inconclusiveness of the first test we decided to have a second paternity test. This time however, in hopes of trying to avoid the mutational mismatch, we tested my husband against the same alleged father. We used a lab local lab that took the samples themselves, ANY LAB TEST NOW.  We also chose a test that used 26 alleles instead of 17 because we were told it would be more accurate.  The results of this test showed a 0% probability of paternity, with the legal standard of 3 mismatches, but with 23 out of 26 alleles matching. We had the professor look at these results also, and again she was concerned that in two of the three mismatches the child showed possible homogeneity. She said that the 0% probability was misleading, that the lab reported 0% anytime there were 3 mismatches due to that being the legal standard.  She was not able to give a percentage of probability this time however, because unlike the first test this lab did not use the standard genetic markers from CODIS, and she did not have access to a program that calculated the probability with the markers that were used.  Her only suggestion, short of re-testing, was that we call the lab and ask for the actual probability percentage. They were unwilling to give that information to us.

 I would like to avoid any more expensive testing and would really appreciate any help or direction you can give me on this matter, as I hope you can imagine our confusion, frustration, and anxiety with one test that we understand to be reporting the alleged father is the biological father; and another test reporting that he is not. I can be reached at (*)

P.S.  I can email test results if you email me!!!!

Sincerely,

Carla




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