The answer to whether DNA results can be wrong is usually no, and very rarely yes, according to existing DNA testing information. Most of the time, unexpected results indicate something real about your family relationships.
While highly reliable, errors in DNA testing can occur, albeit infrequently. It's more common for unexpected results to reflect accurate but surprising genealogical facts. Here's a breakdown:
Accuracy of DNA Tests
DNA tests are generally extremely accurate due to advanced technology and rigorous quality control. The likelihood of a false positive or false negative is low.
Potential Sources of Error
Even with accurate testing, there are still ways that results might seem incorrect. Here's how:
Sample Handling Errors
- Contamination: If a DNA sample is contaminated during collection or processing, it can lead to inaccurate results.
- Mislabeling: Errors in labeling samples can lead to mismatches and incorrect associations.
Interpretation Errors
- Statistical Variations: DNA results are often interpreted using statistical probabilities, which can sometimes be misleading.
- Understanding Complex Relationships: Untangling complex family relationships (e.g., adoption, undisclosed parentage) can be challenging and may lead to initially confusing results.
Biological Factors
- Mutations: Rare mutations in DNA can sometimes interfere with accurate analysis.
- Chimerism: A person with two different sets of DNA (chimerism) may have mixed results.
What To Do if You Suspect an Error
If you receive DNA test results that seem incorrect, consider the following steps:
- Review the Results Carefully: Understand what the results are actually saying before jumping to conclusions.
- Consult a Genetic Counselor: A genetic counselor can help interpret complex results and identify potential issues.
- Retest: If you strongly suspect an error, consider retesting with the same company or a different DNA testing service.
- Consider Alternative Explanations: Before assuming an error, explore other possible explanations, such as adoption or previously unknown family relationships. As the reference states, it is "usually not, and very rarely yes. Most of the time, when you see a result you do not expect, it is your DNA trying to tell you something about your family relationships."
Example Scenario
Imagine someone expects a specific ethnicity to appear prominently in their DNA results, but it's missing entirely. Instead of immediately assuming the test is wrong, they should:
- Review the report carefully.
- Consider that an ancestor might not have been who they thought.
- Consider retesting to confirm.
Conclusion
While DNA tests are highly reliable, the possibility of errors exists. More often than not, unexpected results point to previously unknown information about your family history. Thoroughly reviewing the results, seeking professional guidance, and considering alternative explanations are crucial before concluding that a DNA test is wrong.
