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DNA and genetic testing have been used for decades to establish parenthood. But now, with at-home DNA testing kits like 23andMe available, it is easier than ever to prove paternity.
According to the Cleveland Clinic, DNA testing is considered the most accurate testing method available. It shows the likelihood of a person being someone’s mother or father with about 99.9% accuracy. It also excludes someone as the parent with 100% accuracy.
Using a DNA test to confirm parenthood is an important tool for many reasons.
Of course, there are a variety of legal issues involved. The most common arise due to child support and establishing paternity. But there could be valid reasons for confirming maternity, as well. For example, an adopted child could use a DNA test to identify either biological parent.
Today’s modern tests are based on DNA analysis. These tests are performed at home and tend to cast a wide net. They might be slightly less accurate than a test performed by a doctor, but for a reasonable fee, at-home DNA tests provide a significant amount of information. Some at-home tests are more reliable than others. For instance, 23andME scans hundreds of thousands of genetic markers and provides some of the most comprehensive results from a DIY test.
The cost of a DNA paternity test varies based on the type of test used. A test performed in a doctor’s office and evaluated at a lab costs about $400 to $800. At-home tests are much cheaper and usually only cost about $150.
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More invasive tests conducted by medical professionals can cost more than $1000.
The cost of the test is also based on whether it is performed in-utero, or after a baby is born or as an adult via a cheek swab. Health insurance does not cover DNA testing.
There are a few things you should know if you want to take a DNA test to confirm a biological relationship.
Paternity tests don’t take long. Usually you’ll have results in about 7 to 10 days, depending on the type of test and how long the lab takes to process it.
DNA paternity and maternity tests tend to be extremely accurate. Many have accurate results up to 99.9% confirming someone as a parent. Tests that exclude someone as a parent can be up to 100% accurate.
But this doesn’t mean the tests can’t ever be wrong. The most common reasons DNA testing might be inaccurate include:
If someone intentionally tampers with a test it could produce inaccurate results. The most common type of DNA testing fraud occurs when someone tries to produce a false positive result by tampering with testing material.
Lab errors are rare, but they do occur. In legal situations in which it is necessary to establish parentage beyond a reasonable doubt, the court might order more than one test. This eliminates the risk that an erroneous test due to lab error would negatively impact a situation. A second test can confirm or refute the results from the first and follow-up tests can be ordered based on the second test’s outcome.
If a person’s biological parent is related to the suspected biological parent who undergoes testing, the test results might show a false positive. The more expensive tests performed by medical professionals tend to show more detailed and highlight discrepancies.
For example, a test performed by law enforcement would likely show that the suspected parent is related to the actual biological parent. In contrast, less advanced testing methods throw a wider net over potential relations.
This is the rarest reason for a DNA test to produce inaccurate results. DNA mutations occur when a sperm contains a mutated strand of DNA which causes a child’s DNA to differ from his or her father’s DNA. It’s more common for this to occur as a man ages, but it’s still rare.
DNA tests are a useful tool for proving paternity or maternity. However, they don’t always provide a complete picture. They make a great starting point for identifying potential relations between parents, children, and other family members.
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