We want to provide you with some information on how 23andMe uses your genetic sex, your self-reported birth sex, and your self-reported gender to tailor your account experience.
This article will discuss the following topics:
- Why does 23andMe ask for my birth sex, and how is that information used?
- How is my genetic sex used?
- How is my self-reported gender used?
- Sharing and privacy considerations
- I have a genetic condition that affects my sex chromosomes
Why does 23andMe ask for my birth sex, and how is that information used?
When you register your kit, 23andMe asks you to report your sex assigned at birth. When we analyze your DNA, we also determine a "genetic sex" based on the number of X and Y chromosomes we detect.
23andMe uses one’s self-reported birth sex and genetic sex in a few important ways. One way we use this information is as a part of our laboratory quality control steps. Providing accurate data is a top priority. If someone’s self-reported birth sex doesn’t match what we’ve determined from our analysis of their DNA, we want to make sure that there wasn't an error in processing.
We also use the birth sex that you reported during kit registration or in your Account Settings to help us deliver or interpret your results for certain health, wellness, and traits topics and to provide you with content that applies to you.
Depending on the topic, we may use self-reported birth sex because the result or interpretation depends on your chromosomal sex (typically XX or XY). For example, if you tell us you are female, certain reports will contain information that is relevant for people with two X chromosomes. If you tell us you are male, those reports will contain information that is relevant for people with a single X chromosome.
We also determine whether you receive certain reports based on your self-reported birth sex. For example, if the report is on a condition that impacts certain reproductive organs or covers sex-specific traits, then that report is only shown to people of the birth sex for which that condition or trait is relevant.
Finally, some reports tailor risk estimates to your self-reported sex when the condition is more commonly found in people of one sex. These risk estimates are based on published scientific studies that were done primarily in cisgender individuals.
We understand that sex is not always binary, and that the words "male" and "female" may not accurately reflect an individual's identity. We also recognize that being categorized by birth sex may be an uncomfortable or triggering experience for some people, and we do not mean to delegitimize anyone's gender identity or expression. However, because our reports are based on scientific studies done primarily in 46,XX and 46,XY cisgender individuals, we are unable to provide specific information for other individuals at this time. As new research is conducted and as we learn more, we hope that we'll be able to provide more tailored information to transgender, non-binary, and intersex individuals.
Keep in mind that you can always change the self-reported sex in your profile from within your Account Settings.
How is my genetic sex used?
Genetic sex is the sex 23andMe determines from your DNA analysis, based on genetic markers on the sex chromosomes (X and Y). The sex chromosomes are important for us to consider in a few of our reports. One of our ancestry reports, called a Paternal Haplogroup report, can only be directly generated for an individual with a Y chromosome.
Additionally, our Ancestry Composition report displays a chromosome painting to show where each ancestry assignment is from on a chromosomal level. For people who were determined to be genetically female, there will be two X chromosomes shown in this report, whereas genetically male individuals will only see one X chromosome.
Please keep in mind that the genotyping technology we use to analyze your sample is not designed to pick up genetic changes beyond the types of single variant changes we include in our reports. 23andMe will assign you a “genetic sex” based on your DNA analysis. It is important to note that our genotyping service is not designed to identify intersex conditions even though they may become apparent in individuals that are genotyped by our service. Additionally, 23andMe is neither a diagnostic tool nor a substitute for a physician’s advice. If your primary concern is to identify your genetic sex, we recommend you consult with a genetic counselor.
How is my self-reported gender used?
When you register your kit, there is an option to select your gender. You can also make this selection from within your Account Settings.
This information may be used in a couple of ways. If you choose to opt in to research, your gender may be included but it is always de-identified from your genetic information. Additionally, if you indicate your gender is not the same as your birth sex, you will receive messaging within the 23andMe experience that our health reports are based on your self-reported birth sex.
Keep in mind that you can always change the gender in your profile from within your Account Settings.
Sharing and Privacy Considerations
We recognize that individuals have different comfort levels when sharing personal information with other 23andMe users and have designed our service to give customers control over how much information they share. All sharing features on our site require an individual to opt-in. You may choose to participate in some features that could enable others to infer your genetic or self-reported sex.
DNA Relatives
The DNA Relatives feature is an interactive 23andMe feature that allows you to find and connect with genetic relatives who are also 23andMe users participating in this feature, and to learn more about your family story. This feature is optional; other 23andMe users will not be able to see you as a genetic match unless you opt in to the feature.
If you choose to participate in the DNA Relatives feature, your profile will be shown in your matches' DNA Relatives lists.
When a match views your profile, your profile includes your predicted relationship with that person.
Your Predicted Relationship
The DNA Relatives feature estimates a predicted relationship using the number of segments and percent DNA shared. If you choose to participate in DNA Relatives, or if you establish a sharing connection with another genotyped user, your X chromosome(s) — but not the Y — are analyzed to find any DNA you may share with other participating users.
However, the X and Y chromosomes are not used to define your relationship labels. You can choose if you would like to have masculine, feminine, or gender neutral relationship labels (e.g., brother, sister, sibling) shown to your DNA relatives. You can set your relationship labels by editing your Personal Information in Account Settings.
You can also decide if you want to display your ancestry results and matching DNA segments. If you choose to share this information, it is possible for your genetic relatives to infer your genetic sex. For example, if you choose to show your ancestry results, your profile will also include your ancestry reports, including your maternal and paternal (if applicable) haplogroup assignments. And displaying the locations of your matching DNA segments may allow your relatives to determine your genetic sex.
For a full list of the information that will be displayed in DNA Relatives, review our Privacy and Display Settings in DNA Relatives help article.
Connections
If you choose, you are able to establish sharing connections with other users (including and in addition to, your DNA Relatives matches). This allows both users to view one another's profile.
When connected, your profile includes your predicted relationship with that person, if you have one, as well as any matching DNA segments. You will also be able to choose either an Ancestry Only or Ancestry + Health sharing level.
It is possible for your connections to infer your genetic or self-reported sex from matching DNA segments or from certain shared reports.
Learn more about sharing levels in the How 23andMe Sharing Works help article.
Publishing Reports
If you choose, you can publish and share your reports via Facebook, Twitter, email, or by directly providing a unique link. If you choose to do this, it's possible that the people you share this with may be able to infer your genetic or self-reported sex. For example, if you publish your Ancestry Composition report, whoever you share that with will be able to see your predicted number of X chromosomes. You are able to see a preview of each report prior to publishing so that you can decide if you are comfortable sharing that information.
I have a genetic condition that affects my sex chromosomes
The 23andMe Personal Genetic Service analyzes your DNA at specific points throughout your genome where single letters of the genetic sequence have been shown to differ among individuals. This process is called SNP genotyping, and is not well-suited for detecting missing or extra sex chromosomes in a person, such as Turner syndrome (45,X) and Klinefelter syndrome (47,XXY).
The vast majority of 23andMe Carrier Status* and Genetic Health Risk* Reports are based solely on genes located in chromosomes 1-22 (not the sex chromosomes). Thus, these reports should not be impacted by any sex chromosome abnormality.
However, our test does look at variants on the X chromosome for one of our Genetic Health Risk reports* (G6PD Deficiency Genetic Health Risk Report**) as well as for our Ancestry Composition Report and some of our reports Powered by 23andMe Research. If you have questions about how your genetic condition will impact these reports for you, please reach out to our Customer Care team.
*The 23andMe PGS test includes health predisposition and carrier status reports. Health predisposition reports include both reports that meet FDA requirements for genetic health risks and reports which are based on 23andMe research and have not been reviewed by the FDA. The test uses qualitative genotyping to detect select clinically relevant variants in the genomic DNA of adults from saliva for the purpose of reporting and interpreting genetic health risks and reporting carrier status. It is not intended to diagnose any disease. Your ethnicity may affect the relevance of each report and how your genetic health risk results are interpreted. Each genetic health risk report describes if a person has variants associated with a higher risk of developing a disease, but does not describe a person’s overall risk of developing the disease. The test is not intended to tell you anything about your current state of health, or to be used to make medical decisions, including whether or not you should take a medication, how much of a medication you should take, or determine any treatment. Our carrier status reports can be used to determine carrier status, but cannot determine if you have two copies of any genetic variant. These carrier reports are not intended to tell you anything about your risk for developing a disease in the future, the health of your fetus, or your newborn child's risk of developing a particular disease later in life. For certain conditions, we provide a single report that includes information on both carrier status and genetic health risk. For important information and limitations regarding each genetic health risk and carrier status report, visit 23andme.com/test-info/.
**The G6PD Deficiency Genetic Health Risk report is indicated for reporting of the V68M and S188F variants in the G6PD gene and describes if a person has a variant associated with G6PD deficiency and an increased risk for episodes of anemia. The variants included in this report are most studied in people of African, Southern European, Kurdish Jewish, Middle Eastern, Central Asian, and South Asian descent.