Looking at your genetic data might uncover information that some people find surprising. This information can be relatively benign and even amusing. At other times, the information you learn can have profound implications for both you and your family. 23andMe cannot provide you with an exhaustive list of all the unexpected things you might uncover during your genetic exploration, but in general these things fall into four main categories.
Because our genes are part of our family heritage, genetic information can sometimes reveal things about our biological relationships to other family members. In the process of learning about your genetic makeup and comparing that with others, you may discover relatives who were previously unknown to you. Your genetic profile can lead you to other, distant branches of your family tree.
In a similar way, genetic information can also reveal that someone you thought you were related to is not your biological relative. This happens most frequently in the case of paternity.
Genetic information can also tell you things about your ancestry and origins, and therefore about your relationship to other groups of people across the globe. Sometimes this information will confirm things you already know about your particular heritage or origins. At other times, this information might surprise you, and you might learn that you share a genetic history with unexpected groups.
Different people feel differently about this kind of information; some people are excited about these new connections and others take more time to integrate this information into their sense of self. As with much of the information you might uncover on your genetic voyage, how this new information makes you feel will depend on your personal viewpoint.
Much of the recent press about genotyping services has focused on issues of genetics and health. Each of us carries a large number of genetic variations - from differences at single DNA "letters" to duplications or deletions spanning entire chromosomes. Some of these variations may have little effect on our well-being, or may actually be protective against certain diseases or conditions. Other variations may increase the likelihood of developing a specific disorder.
Learning that your genotype is associated with an increased risk of a particular condition can be difficult, especially if you have seen a friend or family member struggle with a similar issue. One of the potential benefits of having more information is that by working with your physician you may better manage your health. But as a matter of personal choice, some people prefer not to know.
Because genetic information is hereditary, knowing something about your genetics also tells you something about those closely related to you. Your family may or may not want to know this information as well, and relationships with others can be affected by learning about your DNA.
Everyone has different tolerances and preferences for learning information. You might be surprised by a family member who would prefer not to know something you feel is important to share. At other times, you may learn something about yourself, your family, your ancestry, or health-related associations with your genotype that you would prefer to keep private. You may find yourself having to weigh sharing such information with other family members against your own desire for privacy - or their desire not to know.