Genetic testing

What is a genetic exam?

According to the classic definition by Holtzman and Watson (1997), a genetic examination is "the analysis of DNA, RNA, chromosomes, proteins, and certain human metabolites to detect genotypes, mutations, phenotypes, or karyotypes related to hereditary diseases, for clinical purposes."

It is performed in a specialized laboratory and allows the study of genetic variants related to health conditions, drug response, or personal traits. Depending on the size of the changes being sought, different techniques are used:

• <strong>Cytogenetic studies (karyotype)</strong>: detect large alterations, visible when observing chromosomes under a microscope.

• <strong>Molecular studies</strong>: detect very small changes, even in a single letter of DNA. For this, techniques are used such as genotyping with DNA chips or sequencing, which can range from a few genes to the complete genome.

Thanks to these analyses it is possible to obtain information about hereditary conditions, estimate genetic vulnerability to health conditions in which genes play an important role, know how your genes can influence your response to certain medications, and discover your origins.

To perform it, the genetic material of your cells is studied. Many clinical tests use a blood sample, but in tellmeGen, a simple saliva sample taken at home is enough.

We inherit two copies of most of our genes, one from our father and one from our mother. In total, humans have around 20,000 protein-coding genes. Since genetic information is personal and can also affect family, it is advisable to have the support of a professional in genetic counseling when the results require it.

Types of genetic exams:

There are many types of genetic analysis, such as prenatal testing or DNA fingerprinting. These are the ones you can find at tellmeGen:

• <strong>Genetic vulnerability</strong>: identifies genetic variants associated with the development of various health conditions throughout life and estimates your genetic vulnerability to them. It is especially interesting if there is a family history and you do not yet have symptoms. It is valuable information for prevention; any decision about your health should always be made with a healthcare professional.

• <strong>Hereditary Conditions (Carrier Test)</strong>: indicates if you have one copy of a genetic variant that, when two copies are present, causes an inherited disease. Being a carrier usually does not produce symptoms, but it is possible to pass the variant on to your children. If both partners are tested, they can know the probability of having a child with that condition. It is especially useful if there is a family history or if you belong to populations where certain conditions are more frequent.

• <strong>Pharmacogenetics</strong>: analyzes how your genes can influence your response to certain medications: their efficacy, their safety, or the dose you may need. It is information you can share with your doctor to personalize your treatment. Keep in mind that, in addition to genetics, the environment, diet, lifestyle, and your health status also have an influence. Do not start, change, or stop any treatment without consulting your doctor first.

• <strong>Traits</strong>: characteristics that depend to a greater or lesser extent on your genetics and that help you know yourself better: from nutrigenetics to eye color, baldness, tendency to overweight, or different metabolic values.

• <strong>Ancestors</strong>: if you are interested in your family history, ancestry analysis complements what you may know from your family or historical documents. Some patterns of genetic variation are shared among people of the same origin and offer clues about where your ancestors come from. In addition, with DNA Connect you can find relatives who have also taken the test.