Someone may learn that a person they believed was an unrelated stranger shares a close biological connection with them. Another person might discover that a long-held family story does not match the available genetic evidence.
That is why it is worth considering the emotional implications before ordering a consumer DNA test.
Results can affect relationships among parents, children, siblings, and extended family members. They may also uncover information that other relatives did not expect to become public.
Privacy is another important consideration. Depending on the service, users may be able to match with other participants, share information with genetic relatives, or choose settings that influence how their results are displayed.
Anyone considering testing should review the company’s privacy policies and understand that genetic information can reveal facts about biological relatives, not just the person who submits the sample.
What an Unexpected DNA Match Can—and Cannot—Tell You
Although DNA matching can provide valuable clues, a predicted relationship should not be treated as a complete explanation.
Several factors can affect the interpretation:
- The amount of shared DNA: This can help narrow down possible relationships, but different relationships may overlap.
- The family tree: Knowing the ages, locations, and relationships of previous generations can help clarify how a match might have occurred.
- Additional genetic matches: Shared matches with other relatives can help identify which side of a family a connection may come from.
- Historical records: Birth certificates, marriage records, adoption documents, and other records may provide useful context where available.
- The testing service: Different companies may use different methods and labels to estimate relationships.
When the results are unexpected or consequential, a genetic genealogist or another qualified professional may help interpret the findings.
