Buzz
If you're curious about your heritage, searching for relatives, or exploring inherited health and personality traits, the journey often begins with providing a saliva sample in a tube.
Unless you find a discount, expect to spend at least $100. Currently, Ancestry offers their service for $99. 23andme charges $99 for ancestry insights and $199 for a comprehensive package including health and trait analysis. Helix requires an $80 sequencing fee, but additional partner services are needed to interpret the data. For instance, DNAPassport is available for $29. (After your initial Helix sample, you can purchase other partner services without repeating the sequencing fee.)
Companies like 23andme, Ancestry, and Helix request saliva because it’s an easy way to collect DNA. You’ll need to spit multiple times to reach the fill line. Your saliva contains cells from your cheek lining and white blood cells, which are processed in the lab to extract and analyze your DNA.
What Insights Can DNA Provide?
Our 46 chromosomes are essentially long DNA molecules composed of four bases—adenine, thymine, guanine, and cytosine—arranged in a specific sequence that encodes vital cellular information. This genetic blueprint dictates everything from enzymes that metabolize calories to proteins forming muscles, hormone receptors, and even the machinery responsible for DNA replication. If our body produces it, the instructions are embedded in this code.
With billions of chemical letters in our DNA, reading each one remains costly. To address this, companies employ one of two strategies.
Rather than directly sequencing your DNA, 23andme and Ancestry use microarrays—glass chips with tiny spots that glow in red, green, or yellow upon detecting specific DNA patterns. A computer scan generates a list of approximately 600,000 DNA locations and their corresponding letters. Both services offer tools to interpret your results, but you can also download the raw data: Ancestry and 23andme provide instructions for this.
Helix, the lab powering newer services like the one that accurately predicted my children’s hair color, takes a different approach. Instead of targeting specific letters, Helix sequences millions of nucleotides and securely stores this data. Partner services, such as babyGlimpse, access only the necessary information to deliver their results. (While Helix ensures partners handle data responsibly, reviewing their privacy policies is advisable.)
Although Helix gathers more data than 23andme, both often utilize their findings similarly: to identify genetic variants known as SNPs.
Understanding SNPs
Despite our individuality, humans share a vast majority of their DNA. Over 99% of my DNA matches yours, even if we’re unrelated. Interestingly, we share approximately 98.8% of our DNA with chimpanzees.
Since most of our DNA is identical, genetics companies focus on specific regions where variations commonly occur. For instance, I might have two As in a spot where you have an A and a G. (Each of us inherits one DNA copy from each parent, so the A could come from your mother and the G from your father.)
These variations are known as single nucleotide polymorphisms, or SNPs (pronounced “snips”). Some SNPs affect critical protein-building instructions, leading to different protein versions. Others are harmless markers often linked to specific traits. For many SNPs, scientists are still uncovering why they correlate with certain traits, prompting further research.
Even with Helix’s extensive DNA sequencing, many partner services rely on SNPs rather than the full dataset to provide insights. Some services accept data from either Helix or 23andme, giving you flexibility.
Exploring the Possibilities of Genetic Data
After obtaining your genetic data, here are some popular ways people utilize it:
Compare your SNPs with individuals from different regions. This forms the foundation of ancestry tests, which can even reveal connections to ancient populations like Neanderthals or Denisovans.
Identify SNPs linked to personal traits. Discover if you carry genetic markers for lactose intolerance, caffeine sensitivity, or even traits like eye color. Some companies also use your DNA to suggest personalized diets or wine preferences.
Check for SNPs associated with health conditions. While consumer DNA tests aren’t definitive for serious health risks, you can explore your raw data for insights. Always consult a genetic counselor or doctor if you find something concerning.
Upload your raw data to third-party services. Platforms like Family Tree DNA, GEDmatch, or Promethease allow you to connect with distant relatives or delve deeper into health-related genetic traits.
While these applications offer exciting opportunities, they come with significant trade-offs, including serious privacy risks for you and your family. If you’re curious or have already taken the plunge, you now have a better understanding of what happens to your DNA sample after it’s sent off.
