Our DNA is a fascinating blueprint, holding the instructions that shape everything from the colour of our eyes to how we process nutrients. But how much do you know about the role your genes play in your overall health? Here we’ll explore the basics of genetics, how your DNA influences your well-being, and how understanding your unique genetic code can empower you to make informed lifestyle choices towards a healthier you.
What are Genes?
Genes are segments of DNA that carry instructions for making proteins, the building blocks of your body. Think of them as the instruction manual for your body’s functions, influencing traits like metabolism, hormone production, and stress response. Everyone inherits two copies of each gene - one from each parent - making your genetic makeup uniquely yours. Your genes are passed down from your parents, which means you inherit traits (and potential health risks) from your family. For example, you might inherit a predisposition for high cholesterol or an ability to efficiently metabolise certain vitamins. These inherited traits come from combinations of genetic variants, some of which may have protective effects, while others could increase susceptibility to certain conditions.
Your Genes Aren’t Your Destiny
While your genetic code is fixed, its influence isn’t set in stone. Environmental factors like diet, exercise, stress, and sleep can significantly impact how your genes express themselves - a concept known as epigenetics. This means you have the power to make choices that support your genetic strengths and counteract potential weaknesses. Additionally, not all genetic predispositions are "bad" - many inherited traits offer advantages. For instance, certain genetic variants may enhance athletic performance, improve your ability to adapt to stress, or make you more resilient to environmental toxins.
For instance, studies suggest that living a healthy lifestyle can greatly lower the risk of heart disease, even for people with a high genetic risk. For example, those with the highest genetic risk who followed at least three healthy lifestyle habits reduced their risk of heart disease by about 46% compared to those with unhealthy habits1. However, this doesn’t mean all genetic risks can be reduced equally, as the effects depend on the specific genes and lifestyle factors involved.
Understanding Genetic Variants
Genetic labels like A, G, C, and T represent the four building blocks of DNA: adenine (A), guanine (G), cytosine (C), and thymine (T). These molecules are called nucleotides, and they pair up in specific ways to form the rungs of the DNA "ladder", where A pairs with T, and C pairs with G.
The sequence of these nucleotides in your DNA determines the instructions your body follows to build proteins that perform countless biological processes. When you receive genetic test results, you might see combinations like AA, AG, or GG. These refer to the two copies of a gene you inherit - one from each parent. These two-letter labels indicate which versions of a gene you have at a specific location in your DNA, known as a single nucleotide polymorphism (SNP). These small variations are incredibly common - about 10 million SNPs are estimated to exist in the human genome.
The vast majority of SNPs occur in non-coding regions of DNA - areas that do not directly influence the production of proteins. These are often considered "neutral" variations, with no measurable impact on health or function. However, when SNPs occur in coding regions (genes) or regulatory areas, they can influence how genes are expressed or how proteins function.
When interpreting genetic results, you may come across terms like wild-type, heterozygous, and homozygous:
- Wild-Type (i.e. AA): This is the "normal" or most common version of a gene in a population. It often indicates typical function with no known alterations in the gene sequence that affect health or biological processes.
- Heterozygous (i.e. AG): You have one normal copy and one mutated (variant) copy of a gene. Depending on the gene, this might result in partial changes to its function. For example, you may still produce a functional protein, but at a reduced level or with altered activity.
- Homozygous (i.e. GG): You have two mutated copies of the gene, which can amplify the effect of the variant. This may significantly impact how the gene - and the protein it produces - functions. In many cases, homozygosity can result in more pronounced traits or risks compared to heterozygosity.
As an example, for genetic mutations linked to lactose tolerance, being heterozygous might mean you can digest small amounts of lactose, while being homozygous might result in complete intolerance due to reduced function of the enzyme produced.
Why Your DNA Matters
Understanding your genetic predispositions gives you a powerful tool for tailoring your diet and lifestyle, as well preventative care strategies. Armed with this information, you can make choices that align with your genetic strengths, mitigate potential weaknesses, and pave the way for a healthier, more vibrant life. For example, studies have shown that individuals who tailor their diets based on genetic testing lose 33% more weight on average than those following a standard diet plan.
Your genes are the starting point for your health journey - not the destination. Understanding the genetic "hand" you've been dealt empowers you to make informed decisions about your health and turn potential risks into opportunities for proactive management. Explore how understanding your DNA can empower you to make smarter, more personalised choices for a healthier, happier life with our myDNA Comprehensive Health Report.
