DNA genetic testing: what your genome reveals

Your DNA holds two stories at once: your family's, which reaches back a very long way, and your own, which is still being written. A genetic test reads both. It tells you which regions of the world your ancestors came from, which variants you inherited that may matter for your health or your children's, and how your body is likely to respond to certain medications. At Laboratorio Aclimu we do this with Atlas, our genomic study. This article explains what it measures, what it reports and how it works.

What does a DNA genetic test read?

Any two people share 99.9% of their DNA. What makes us different lies in a tiny fraction: individual positions in the genome where one person has one "letter" and another person has a different one. These differences are called SNPs (single nucleotide polymorphisms), and they are what a DNA test looks for.

Atlas uses a genotyping chip: a slide with probes that recognize each of those positions and read which letters you carry at each one. The Atlas chip reads 714,692 positions of your genome in a single run. This is not the same as sequencing the whole genome — which reads every letter, one by one — but it is enough for the questions the report answers, and each section states how far what the chip sees actually reaches. If you want to understand better how it works, Atlas has a genetics-from-scratch guide.

What does the Atlas report include?

• Ancestry: the make-up of your DNA by regions of the world, each with its own margin of uncertainty, along with the migration routes of your maternal lineage and, if the sample carries a Y chromosome, your paternal lineage too.
• Predispositions: conditions for which your genotype changes the probability of developing them.
• Carrier status: recessive or X-linked conditions that you could pass on to your children without having them yourself. This is especially useful information for anyone planning a pregnancy.
• Polygenic risk: common conditions in which no single variant carries the weight, but rather the sum of many, grouped by type: cardiovascular, metabolic, autoimmune, oncological and others.
• Pharmacogenomics: how you are likely to respond to specific medications, with a traffic-light rating by drug and by gene. This is the section with the strongest clinical backing: most of it follows the international guidelines of the CPIC consortium, and each card states which source it comes from.
• Nutrigenetics and traits: lactose tolerance, caffeine and alcohol metabolism, muscle fiber type, sleep and other traits that are read out of interest.

You can browse a complete sample report before you decide.

Every result tells you how much evidence backs it

Not all genetics carries the same backing, and an honest report has to say so. That is why in Atlas every finding comes with its level of evidence: from established clinical use — there are official recommendations for doctors that can change a course of action — to the exploratory, which is there out of interest rather than medical usefulness. That way, on each card, you know how much weight to give what you read, and which sources it was calculated from.

Genetic test vs. medical genetic study: the difference

Atlas is not a diagnostic study. It reports predispositions and drug response, not diseases: if you have symptoms, the right step is a medical consultation and a targeted study, and any finding with clinical implications is confirmed by a validated method before a decision is made. Nor does it replace a genetic study ordered by a doctor: if your family has a history of hereditary cancer, for example, the chip may find a known pathogenic variant, but it cannot rule them all out, and a dedicated gene panel is the appropriate test. For those cases there are the studies from our genetics and genomics area, such as gene panels and the clinical exome.

How it's done

The sample is a swab of the inside of the cheek: no blood, no fasting and no medical order, from the age of 18. The only preparation is not eating, drinking — not even water — smoking or brushing your teeth in the 30 minutes beforehand, because food residue and liquids contaminate or dilute the sample.

1. You book online at atlasgenomico.com and choose how to give the sample: at the laboratory, in five minutes, or at home with a kit delivered to a pickup point near your address.
2. You take the sample and, if you use the kit, you register in your account the code printed on the box: that is what links the sample to your name. The tube travels identified only by that code.
3. The laboratory processes it: DNA extraction, genotyping, quality control and interpretation. If the sample does not pass the controls, the report is not issued and we ask you for a new one.
4. You receive the report in your account, around 30 days after the sample reaches the laboratory. It does not expire: you can view it again whenever you like.

Your genetic data

Genetic data is sensitive personal data, covered by Argentina's Personal Data Protection Act (Law 25.326). Before the sample is taken you sign an informed consent that you can read in advance. The data is not sold or transferred to third parties, and genotyping, quality control and interpretation are all done at our laboratory in Recoleta.

At Laboratorio Aclimu

Atlas is the genomics service of Laboratorio Aclimu (Marcelo T. de Alvear 2337, Recoleta, Buenos Aires): it is interpreted by a laboratory with more than 30 years of experience and ITAES accreditation, not an app. It is a private (particular) study — not covered by Argentine insurers (obras sociales) or prepagas — and you arrange it directly at atlasgenomico.com, where you will also find the current price and the frequently asked questions.

This article was reviewed by the Laboratorio Aclimu team. The information is for general guidance and does not replace a consultation with your doctor or health professional.

Frequently asked questions

What is a DNA genetic test?

It is a study that reads specific positions in your DNA where people differ from one another. From those readings it estimates which regions of the world your family comes from, which variants you inherited that may affect your health or your children's, and how you are likely to respond to certain medications.

How is the sample taken?

With a swab of the inside of the cheek: no blood and no fasting. The only requirement is the 30 minutes beforehand with nothing to eat or drink — not even water — and no smoking or brushing your teeth. It is done at the lab in five minutes, or at home with the kit.

Can it diagnose a disease?

No. Atlas has no diagnostic value: it reports predispositions and drug response, not diseases. If you have symptoms, the right step is a medical consultation and a targeted study, and any finding with clinical implications is confirmed by a validated method before any decision is made.

Do I need a doctor's order?

No. From the age of 18 you can book it directly at atlasgenomico.com, with no medical order and no referral. It is a private (particular) study, so it is not covered by Argentine insurers (obras sociales) or prepagas; you arrange and pay for it yourself.

How long does the report take?

Around 30 days from the moment the laboratory receives your sample. The report then stays in your account and does not expire: you can go back and view it again whenever you like, or open it with your doctor during a consultation.

References

1. MedlinePlus, U.S. National Library of Medicine (NIH). Genetic testing. Available at: medlineplus.gov
2. National Human Genome Research Institute. Single nucleotide polymorphism (SNP). Available at: genome.gov
3. National Human Genome Research Institute. A Brief Guide to Genomics. Available at: genome.gov
4. Clinical Pharmacogenetics Implementation Consortium (CPIC). CPIC guidelines. Available at: clinpgx.org
5. National Center for Biotechnology Information (NIH). ClinVar. Available at: ncbi.nlm.nih.gov
6. Argentina.gob.ar. Personal Data Protection Act (Law 25.326). Available at: argentina.gob.ar