Decoding our Blueprint: How understanding our DNA today can protect our family’s tomorrow

1. DNA: Our Body’s Instruction Manual

Imagine entered a massive library, the shelves contain thousands and thousands of books, except that this library is unique; it belongs to every one of us. This massive library is actually our genome, consisting of 23 pairs of books. Every person has the same “chapters”, which we call ‘genes’, and these genes are the instruction manual for our bodies; they determine everything from the colour of our eyes to the way our hearts beat. While we all have the same chapters, each one of us carries two versions of every book; one we inherited from our mother’s shelf and one from our father’s. In science, we call these different versions alleles. This inheritance is perfectly split in half to create a unique “edition” of the library that belongs only to each one of us. When we look closer into the text inside our books, we find tiny spelling differences which we call ‘variants‘. When we hear the word “mutation” most of us tend to think of something negative, but in the lab, we see them as natural changes. In fact, we share 99.9% of the same DNA; it is that remaining 0.1% of this variation that writes our unique health story.

Most variants are benign, like the difference between using the spelling “color” and “colour”, they are harmless and don’t change the story’s meaning. However, when we consult a genetic counsellor, we look specifically for ‘pathogenic variants’, which are critical spelling errors that actually change the instructions for how our bodies should function. Genetic counselling at the very base is like having a professional “librarian” help us navigate these shelves, reading our history to protect our future.

2. Planning for a Healthy Family

The story of our library becomes even more important when we decide to share it with a partner. We all have “hidden chapters”, which are recessive traits that don’t affect us personally because we have another, “correct” copy of that book to rely on. People with hidden chapters that are pathogenic are known as silent carries. In cases where two parents contain a pathogenic variant in the same gene, there is a 25% risk that their child will contain two copies of the misprint within the child’s DNA. Nowadays, molecular screening can be used to “proofread” our books before or during pregnancy. Recognizing these unspoken chapters early puts us one step ahead of uncertainty and one more step on to empowerment, providing families with the information they need in order to give their children the best possible health start.

In Mauritius, inherited conditions such as Thalassemia are still very common, which makes genetic counseling a crucial part of family planning. Many people can carry a defective gene without being aware about it because they are completely healthy. However, if both parents carry the same altered gene, there is a higher chance that their child may inherit a serious disease.

Family history often gives important clues. Repeated abortions, relatives needing frequent blood transfusions, or several family members affected by the same illness can all point toward an inherited condition. Genetic counseling can identify these risks early, even before pregnancy.

Most importantly, it gives families peace of mind. Instead of facing uncertainty or unforeseen circumstances later, couples can make informed decisions with confidence and preparation. Knowing the risks beforehand allows families to take preventive steps, seek proper medical advice, and protect the health of future generations through informed and proactive care.

3. Liquid Biopsies: The Future in a Blood Drop

One of the most amazing changes in recent years has been the way in which we are reading these books. Historically a genetic “page” would have had to involve invasive procedures such as surgery or long needles. But molecular biology has found a shortcut: Liquid Biopsy.

As we age and mature, little bits of our genetic “torn-out pages” are released into our bloodstream. We call this Cell-Free DNA (cfDNA). Now, we can use a simple and safe blood draw to “fish” these fragments out of an expecting mother’s blood to screen for chromosomal health of a developing baby (NIPT). In the battle against cancer, we search for Circulating Tumor DNA (ctDNA), the microscopic ‘smoke’ of a tumor, that we would look for before it would ever appear on an X-ray. A method which we can refer to as reading the secrets of the library without disturbing the building.

4. Is it in the Family? Understanding Cancer Risk

It is vital to understand how “ink spills” happen in our library. The majority of cancers are somatic in nature which means they are damage to the DNA that occurs accidentally over time. These “smudges” stay in one specific tissue and are not passed down to your children. Approximately 5% to 10% of cancers, however, are Germline. This means that the error was entered into the master blueprint of the library that we’ve all been born with; an error that is present in every cell. When a mutation in such genes, like BRCA1 or BRCA2, is inherited, our body’s own “repair crew” is like missing instructions on how to repair damaged pages. By identifying these inherited risks, we aren’t just waiting for bad news; we are using that knowledge to trigger preventative care that can stop a smudge from becoming a crisis.

Cancer is not always caused by bad luck only. In some families, the risk of developing certain cancers can be passed down through genes from one generation to another. Recognizing these inherited risks early can help doctors detect cancer in earlier stages or even prevent it altogether.

There are several warning signs that may suggest an inherited cancer risk. These include cancers appearing at a young age, especially before 50 years old, multiple relatives affected by the same type of cancer, or one person developing more than one cancer during their lifetime. Such patterns may indicate changes in genes that normally help repair damaged cells and protect the body from tumors.

Once a high risk is identified, doctors can create a personalized follow up plan. This may include earlier and more frequent scans, regular checkups, or preventive treatments depending on the situation.

Genetic counseling changes cancer care from simply treating disease to preventing it. It gives families the knowledge and understanding needed to take action early and potentially save lives.

5. Solving the Medical Mystery (Rare Disease)

For many patients with rare genetic diseases, the hardest part is not only the illness itself, but the long march towards answers. Some people spend years visiting different hospitals and specialists without ever being told exactly what condition they have. This journey is often frustrating, exhausting, and emotionally draining for both patients and their families.

Today, advances in genetic testing are helping solve these medical mysteries. One important test is called Whole Exome Sequencing, or WES. It studies the parts of our DNA that contain the instructions for making proteins, where many changes, which cause diseases, are found. By examining thousands of genes at once, doctors can identify the exact genetic change responsible for unexplained symptoms.

Getting a diagnosis can completely change a patient’s life. It can prevent unnecessary tests, tailor a better treatment strategy and help families better understand what to expect in the future. It also connects patients to support groups and research communities around the world, reminding them that they are not alone in their journey.

6. More Than Just a Lab Report

A genetic test result is much more than a sheet of medical data. Words such as “risk,” “mutation,” or “positive result” can feel frightening and confusing without proper explanation. This is why genetic counseling is so important. Counselors help patients and families understand what the results truly mean for their health and future.

For example, being told that someone has a higher risk of developing a disease does not always mean they will definitely become sick. Genetic counselors explain these risks clearly and help families make proper decisions without unnecessary fear or panic.

Many people also worry about privacy and whether their genetic information could be misused. Counseling helps address these concerns by explaining how medical information is protected and kept confidential.

Most importantly, genetic counseling brings a human touch to modern medicine. Behind every test result is a person, a family, and a story. Beyond science and technology, counseling offers emotional support, guidance, and reassurance during moments that can often feel uncertain and overwhelming.

7. Conclusion: Your Health, Personalized

Precision Medicine isn’t the use of a one-size-fits-all treatment model anymore. We examine your particular library and know exactly which treatments your body has been programmed to react to. Genetic counseling isn’t about finding what’s “wrong”; it’s about using your data to live a longer, proactive life. Our DNA contains a story; one that we can all read, but genetic counseling makes it possible to understand and to write a healthier chapter in the future.

About the authors

Nikhil Gobin

Nikhil is a final-year medical student at SSR Medical College, passionate about precision and preventive medicine, dedicated to making medical knowledge clear, accessible, and meaningful for all.

Sarah Bibi Mungly

Sarah Bibi Mungly is currently completing her MSc in Life Sciences, with a specialized research focus on breast cancer epigenetics. She is passionate about leveraging molecular insights to advocate for early and accessible cancer detection.