Monthly Archives: October 2019

The Reliability of Home DNA Test Kits: Can You Trust Them for Health Not Ancestry?

Genetic genealogy is a burgeoning industry with millions of users signing up for these types of services. Companies like AncestryDNA and 23andMe are leaders in this field. Deoxyribonucleic acid (DNA) houses a phalanx of data that defines every single individual. There are some 23 pairs of chromosomes and 3 billion+ letters of DNA. The overwhelming percentage of DNA (97%) features repetitive sections of coding and control regions. Even more surprising is the fact that a certain amount of DNA is irrelevant; the result of evolutionary processes that have rendered them redundant. 

From a rudimentary perspective, most everyone understands that many genes are inherited. During the 1980s, biologists had discovered mutated genes that created faulty proteins, thereby helping the scientific community to understand the functionality of things like ALS and cystic fibrosis. Thanks to the dramatic advancements in technology, it is now possible to discern the genomes of scores of people at extremely low costs. Our access to data is ostensibly unlimited, and the scientific community has answers to the most pressing questions, including disease, human evolution, and inheritance. The profundity of this information is unparalleled, and its origins can be traced back to the Human Genome Project. We now know why we are what we are as individuals, and collectively as a species.

Technological Prowess Takes DNA Testing to the Mainstream

A quantum leap in technology has facilitated dramatic cost decreases in DNA testing, sequencing, and commercial viability. There are scores of DNA testing companies offering home DNA kits for health and ancestry. The alacrity with which new companies are surfacing is surprising, yet not unprecedented. Nowadays, all that is required is a vial of saliva or a blood sample for DNA sequencing. The accuracy of these DNA home test kits depends upon a variety of factors. Firstly, it’s imperative to ascertain whether the sequencing has been accurately conducted. Secondly, many false positives have been determined after the data was retested. A particular point is worth mentioning in this regard: DTC genetic tests target specific areas of the human genome, not the entire genome. Put differently, DNA testing companies do not all look at the same variant of the gene when specific elements are coded.

Genetics overall does not define anything specific; it is based on probabilities. In other words, it would be foolhardy to assume that a genetic test would indicate a predisposition towards a disease especially if it is not conducted in a clinical setting. Genetic experts routinely caution clients about the merits of interpretations of genetic tests, given that most of the data points towards generalities which cannot be taken as holy writ. While people with Parkinson’s may display certain characteristics, it doesn’t mean that everyone who has those characteristics in their genes will develop Parkinson’s. This is where the interpretation of genetic coding, and health-related matters becomes difficult.

It is safe to assume that the general profile of someone who is likely to have a heart attack may be that they are obese, have an unhealthy diet with lots of saturated fats, drink, smoke, and are sedentary. However, it doesn’t mean that somebody who checks all those traits, or most of them, will have heart attack. There are many fitness enthusiasts who don’t smoke, drink, or live unhealthy lifestyles who have sudden, fatal heart attacks. What geneticists, doctors, and lay people can agree on is that you certainly shouldn’t lead an unhealthy lifestyle if you want to avoid a heart attack. While you may have a genetic predisposition towards having a heart attack, your lifestyle choices are probably more important than what the test results indicate.

Are Home-Based DNA Test Kits for Health Accurate?

So, how do home DNA tests work? Customers simply purchase a home DNA kit from a company and provide a swab of cheek cells with a Q-tip or a blood sample by using a lancet. These samples are then safely and securely sealed and mailed off to the DNA testing company.  The rapid and widespread popularity of home-based DNA test kits for ancestry certainly adds an exciting element to the human genome. Less common is the use of home-based DNA test kits for health purposes. A great degree of caution is advised when using DNA testing for health purposes. Health experts are increasingly concerned about the way that results are being interpreted, and the number of false positives that are being generated. Having said that, tremendous progress is being made in this area, and provided that medical professionals are involved in the process, the accuracy of testing and interpretation of results could certainly merit attention.

Many people are now turning to DNA test kits for the purposes of detecting health issues. Health professionals have no reservations about recommending home-based DNA test kits for ancestry purposes, but they are a little reluctant to endorse them for health and wellness reasons. 23andMe was given the stamp of approval by the FDA (testing for BRCA1 & BRCA2 genes) in 2018.  The problem arises from the fact that error checking is problematic. Home-based DNA health-oriented test kits are susceptible to inaccurate readings and this could either downplay or overinflate the importance of a result. The interpretation can only be conducted by a clinical lab and doctors. Unfortunately, many home-based DNA test kits for health concerns do not examine a broad panel of possibilities – they are limited to specific areas which may not be sufficient, or appropriate for testing of a specific health concern.

In summation, the ubiquity of home-based DNA test kits for health purposes shows tremendous promise. The technology is certainly available to deliver much more information than we ever thought possible. However, it is incumbent upon the user (customer) to correctly interpret the information with the services of a healthcare professional. Further, it is important to understand the scope of testing that is conducted, and areas that may be overlooked by the DNA testing companies. Many markers of diseases exist; this doesn’t mean that a person will develop the disease, nor does it mean that they have the disease, or a predisposition towards an illness or condition.