If you’re reading this, you’ve won the genetic lottery. Your genetic material has survived 3.8 billion years of adaptational pressures to get where it is in your cells today.
There is only one type of technology that has endured the pressures of billions of years on earth: our DNA. This human technology is greatly accountable for who we are and what we do: our appearance, personal characteristics, and even our athletic traits.
DNA is more complex than any of the new innovations or products on the market today. Over 3 billion letters in our human code are responsible for building around 25,000 genes that make you who you are. This 3 billion letter narrative contains the instructions for our endless qualities; both physical and psychological.
But this material that has been progressively changing for billions of years was only discovered 72 years ago. DNA has been around 53 million times longer than the time we’ve been analyzing it. Here we explore how the field of genetics unraveled.
A Brief Overview of Genetics
The field of genetics was not born from looking at cells, or even humans. An Austrian monk named Gregor Mendel tinkered with pea plants during the mid-1800s between teaching science classes in a monastery. By crossing pea plants with distinct physical traits, he discovered dominant and recessive patterns of inheritance, which still apply today to human traits such as eye colour and also human diseases like cystic fibrosis. Mendel demonstrated that the traits of the peas, like color or shape, were inherited in different packages, which we now refer to as genes.
Mendel’s extraordinary discoveries were initially dismissed and criticized by academics. His findings were later re-discovered after his death in the 1900s by several other scientists who replicated his experiments in animals such as fruit flies to support his claims.
The Elusive Heritable Material
Before genes were discovered and heritability was described, scientists understood that there was some form of material that was being passed down from generation to generation, but they didn’t know exactly what it was. Scientists were unsure if it was protein, enzyme or another substance that was responsible for inheritance.
Before DNA had a name, while the concept of a cell was still being debated, DNA was discovered by a Swiss doctor named Friedrich Miescher in 1869. Miescher collected white blood cells from discarded hospital bandages and isolated DNA out of the nuclei of the cells. At this stage in time, DNA was dubbed the substance nuclein. It took over 50 years before Phoebus Levene identified the individual structure of each DNA unit, suggesting that DNA consists of a long string of individual nucleotides: the A’s, G’s, T’s and C’s in our genetic code.
Multiple groups of scientists in the mid-1900s explored the idea of heritability and sought to find the cause for the inheritance of similar traits in organisms. In 1944, Oswald Avery and colleagues added a pivotal piece of evidence to the genetics puzzle, they reported that DNA carried the genetic information in bacteria responsible for causing disease (2).
By the 1950s, there was considerable evidence for DNA being the key genetic material. This persuaded British scientists James Watson and Francis Crick to race other researchers like Rosalind Franklin and Maurice Wilkins to deduce the structure of DNA. Watson and Crick published the paper describing the double helix structure of DNA in 1953 (3), and shortly after helped solve the mystery of how the machinery in our cells read DNA to create proteins - the physical manifestation of our DNA (4).
Watson, Crick, and Wilkins won the Nobel prize for the discovery of the double helix structure of DNA in 1962. Whether Franklin would have been nominated for the Nobel if she were alive is still debated to this day.
From the Discovery of DNA to Today
Multiple advancements in the 1990s propelled curiosity into unraveling the human genome (see timeline at end of article). The Human Genome Project (HGP) was officially launched by the US government in 1990, and was declared complete in 2003. The completion of the project meant that scientists had catalogued every nucleotide letter in the human genetic code, about 3 billion. With the human genome sequence publicly available, the floodgates opened for genetic research in all disciplines including health and disease, and perhaps more controversially, sports genetics.
The ACTN3 gene, or “sprint gene” was first associated with elite athletic performance in 2003, with the finding that elite sprinters possessed the power variant of the ACTN3 gene more frequently than non-athletes (5). This discovery was the motivation behind some companies offering the general public a genetic test for ACTN3, and only ACTN3, at a premium, and in the context of talent identification (We discuss in an earlier post why this is not the goal of sports genetics).
What’s important to note is that ACTN3 is not the sole discriminator of athletic ability, nor are the other 50-plus reported genetic markers associated with athletic traits. Although ACTN3 is associated with elite power performance, there are still many world-class athletes who do not carry the favorable variant of the gene (6). Physical traits like powerful muscle contractions are a result of a complex interplay between multiple sets of genes, not to mention the athlete’s environmental conditions such as nutrition, motivation and coaching.
Despite the exaggerated claims made by scientists in the past, the power of genetics can be applied successfully and practically in sport. For example, our collaborators at Stanford University have reduced injury rates by up to 44% in triathletes who had their genetic profile revealed to them. Even our own CrossFit athletes benefit from understanding their genetic profile, simply by changing up their approach in challenging workouts.
Although the understanding of our genome increases every day, it’s far from complete. New genes are discovered almost daily, the understanding of how genes are expressed is changing, but with improved sequencing techniques the future is bright. Sports genetics is a small part of the genetic research pie, but we believe it has the ability to translate potential into performance.
- Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K., & Walter, P. (2002). Molecular Biology of the Cell (4th ed.). Garland Science.
- Avery, O. T., Macleod, C. M., & McCarty, M. (1944). Studies on the chemical nature of the substance inducing transformation of pneumococcal types : induction of transformation by a desoxyribonucleic acid fraction isolated from pneumococcus type III. The Journal of Experimental Medicine, 79(2), 137–158.
- Watson, J. D., & Crick, F. H. (1953). Molecular structure of nucleic acids; a structure for deoxyribose nucleic acid. Nature, 171(4356), 737–738.
- Crick, F. H., Barnett, L., Brenner, S., & Watts-Tobin, R. J. (1961). General nature of the genetic code for proteins. Nature, 192, 1227–1232.
- Yang, N., MacArthur, D. G., Gulbin, J. P., Hahn, A. G., Beggs, A. H., Easteal, S., & North, K. (2003). ACTN3 genotype is associated with human elite athletic performance. American Journal of Human Genetics, 73(3), 627–631.
- Lucia, A., Oliván, J., Gómez-Gallego, F., Santiago, C., Montil, M., & Foster, C. (2007). Citius and longius (faster and longer) with no alpha-actinin-3 in skeletal muscles? British Journal of Sports Medicine, 41(9), 616–617.