A major factor that impacts everyone’s health is their ancestry. Your ethnicity plays an important role in assessing risk for certain diseases. But ethnic background can be difficult to determine. The modern definition of race in the context of health research is a fluid concept used to define groups in larger sets of population, incorporating ancestry, genetic makeup, expressed phenotype, as well as factors such as socioeconomic status, healthcare availability/accessibility, and social identity. In other words, it’s complicated. Utilizing a genome test to better understand the genetic makeup of an individual helps medical professionals contextualize these complex factors and implement targeted preventative treatments.
One example of how health researchers look at genetic makeup in different groups is the study of Tay-Sachs disease, a recessive genetic disorder that causes premature cell-death in the brain. This leads to physical and mental deterioration starting at six months and usually results in death by age four. Currently, there is no cure or treatment. Tay-Sachs appears in three different ethnic populations on average more than others, and each group has a different genetic cause for the higher-than-average occurrence. Researchers have traced the genetic history of a Tay-Sachs causing mutation in the Cajun population to a French couple from the 18th century. French Canadians from Eastern Quebec and with an Arcadian pedigree have a higher chance of carrying two different mutations that lead to Tay-Sachs affliction. These mutations do not trace back to the same French populace, suggesting a different ancestry. Ashkenazi Jews carry an insertion mutation in higher prevalence than other populations that leads to Tay-Sachs. The genetic background of this disease is complex, but large scale studies have only given us a very broad measure of individual risk for such diseases.
Assessing the impact ancestry may have on individual health can be complicated. Going back to Ashkenazi Jewish ancestry, a host of genetic screenings are already recommended, including screens for Usher Syndrome, Spinal Muscular Atrophy, and Cystic Fibrosis. A whole exome test can replace all of these individual screenings at once, while looking for many other mutations that affect overall health. What if each parent is from different distinct ethnic populations? What does that say about risk for certain genetic diseases? A whole exome test can make that determination very simple. In the case of Tay-Sachs disease, it is an autosomal recessive genetic disorder, which means that if both parents carry the mutation there is a 1 in 4 chance their child will have the disease, while a carrier is completely unaffected. A genetic test will reveal if the patient is a carrier, even when the patient doesn’t know their complete family history or exact ancestry. A whole exome test is so robust that it will pick up on all mutations that are common within a certain group, whether or not the patient is aware of their genetic connection to that population or not.
High-depth and accurate genomic testing is a boon to population health studies, allowing us to easily find and categorize common disease-causing mutations within distinct groups. This allows for a greater understanding of how genes express themselves in certain populations, which leads to broader implementation of preventative treatments given known ancestry. Meanwhile, as genomic medicine is further integrated into modern healthcare practice and more people get sequenced, we can target preventative measures to individuals based on their own genetic makeup. Knowing your ancestry and family history is important for determining your risk, but genetic information complements, expands, and will ultimately replace it. To these ends New Amsterdam Genomics is committed to sequencing as many people as possible, bringing to fruition the full capability of genomic medicine to positively impact the health of our global society.