Genetic Information you share with others could be used against your interests.
Genetic nondiscrimination laws and why it should matter to you
First, consider the true definition of Privacy: (noun) the state of being free from public attention. Next, consider the definition of Information Privacy: the right to have some control over how your personal information is collected and used. Now, consider Genetic Information Privacy: there is no such definition.
Some laws limit how the information can be used, but none truly protects privacy. And that may not even be possible, because genetic information is unique to every individual. It cannot be de-identified; even if separated from obvious identifiers like name and Social Security number, it is still forever linked to only one person in the world.
There are two federal laws that deal with genetic information; GINA (the Genetic Information Nondiscrimination Act of 2008) and HIPAA (Health Insurance Portability and Accountability Act). GINA is essentially an anti-discrimination law that has nothing to do with privacy. It prevents group health and Medicare supplemental plans from using genetic information to discriminate against you when it comes to insurance. However, this law does not prevent genetic information to be considered when applying for life, disability, or long-term care plans. GINA also does not apply unless the employer has more than 15 employees.
HIPAA National Standards
HIPAA established national standards to protect individuals' medical records and other personal health information and applies to health plans, health care clearinghouses, and those health care providers that conduct certain health care transactions electronically. In 2013, the HIPAA Omnibus Rule amended HIPAA regulations to include genetic information in the definition of Protected Health Information (PHI). It also prevents use of the data in underwriting for all other types of health insurance plans, but still not for life, disability, or long-term care insurance. Excluding long-term care insurance guarantees that anyone with a tested genetic predisposition to Alzheimer’s, for example, will be uninsurable. According to the definition, genetic information includes your genetic tests and a family member’s, your or a family member’s fetus or embryo, and evidence of a disease in a family member.
One major problem is that GINA only prohibits discrimination based on genetic information about someone who has not yet been diagnosed with a disease; that is, the disease is not yet "manifest." Today there are many tests for genetic markers that may—or may not—be precursors of a disease and also may mean that you could benefit from preventive treatment. If the presence of genetic markers is considered a “manifestation” of a disease, then neither GINA nor HIPAA applies to the information.
Note: At this time, other genetic testing companies/businesses are only self-regulated and can sell their genetic database at will. This allows them to market and sell genetic testing kit for a small cost because they make much more money selling your genetic data in large chunks.