At present there is a lot of talk about genetic analysis, giving rise to many sometimes wrong ideas and even hoaxes. Especially when it comes to online genetic analysis, direct to the consumer. In this post, I will try to answer doubts, questions or inaccuracies in a simple and clear way that have come to us both directly and through social networks.
I did a genetic analysis to find out my ancestors at a cost of about €100 and it predicted a very high risk of cancer. What should I do?
There are multiple genetic tests. When they cost about €100, there is a strong probability that the study is carried out based on a genotype. To carry out any genetic study, it is necessary to extract part or all of the DNA code.
Good practice determined by recognized medical and scientific entities such as the American College of Medical Genetics and Genomics (ACMG) and the FDA recommend that in order to determine health predispositions, one must look at a specific complete gene or a series of entire genes; or even better, all the genes (exome) of the person.
Because it is considered that a genotype is not enough information to draw conclusions and the risk of false positives increases.
Who decides which genes should be studied?
The most appropriate person is a qualified genetic counselor as recommended by the European Society of Genetics or the Spanish Association of Human Genetics.
For each risk that is sought to be answered or that is suspected, there is a specific analysis that should be carried out. For this reason, at medmesafe, a genetic counselor always prescribes the test that he considers most appropriate according to certain criteria that he studies during a genetic counseling consultation.
Why not generalize genome sequencing? From the exome?
A nuance before launching into a simple explanation. Depending on the technology used, the quality of the sample, the sequencing: the extraction of the DNA code can be more or less precise. There are accreditations and quality certifications to guarantee the quality of the work of laboratories such as CLIA, ISO standards, etc. At medmesafe it is our Scientific and Ethics Committee that selects the laboratories with which we work.
Current technology allows sequencing a whole genome (WGS) but leaves some “non-exploitable zones” for now. Therefore, from a sequenced genome, some areas can be read perfectly and others less so. To this day, the interpretation of a genome cannot have diagnostic value. However, it is a good starting point to understand what we are made of and a series of information related to our authenticity.
On the other hand, whole exome sequencing (WES) is more accurate. In many cases, different genes are involved in calculating the risk of disease. With the generalization of massive sequencing and with the decrease in the cost of sequencing, the tendency of these analyzes is to study more genes for less money.
So one day we explore the entire genome?
Of course. And for different reasons:
The quality of the sequencing is increasing.
The cost of analysis is going down.
The amount of data that we know how to interpret is much greater with each investigation that is carried out.
Why do direct-to-consumer tests generate so much noise, fear, debate?
Above all, because when an online test is purchased, the user is not usually accompanied by a qualified expert. Having raw results without explanation generates stress. For this reason, at medmesafe we believe that at the moment genetic counseling by an expert professional is essential to guide and answer all doubts.
Second, because as I explained earlier, it is bad practice to draw conclusions about the consequences for a person’s health using such partial information.
Finally, because your DNA code is unique. These data are some of the most sensitive data of a person. Having this data stolen is very serious. Having a credit card stolen, you cancel the old one and change it for a new one. But you can’t change your DNA.
If you have more questions, doubts or if you also want to make your contribution to scientific dissemination around genetics/genomics to promote predictive, personalized, precision medicine based on good practices, do not hesitate to exchange on our networks: facebook, twitter , linkedin, or contact us through our contact form or at + 34 911 284 591.
CEO of medmesafe