The Secrets in Our Genes

One evening in 2014, Alice Syam was wandering through queueing crowds and lively stalls at an exhibition in Pune with her husband when an executive approached her. “He said that a woman of my size would greatly benefit from a unique health test they had to offer,” she laughs. At 85 kgs, Alice was tall, well-built, and least worried about her weight or proportions. She was, however, bothered by persistent body ache, joint pain, irritable bowel syndrome, and a host of other health concerns that had plagued her over the years. Just a few months ago, she self-diagnosed these as symptoms of gluten intolerance after reading an article on Novak Djokovic’s experience with gluten sensitivity and celiac disease. 

“At that time, the test proposed by the executive cost `17,000. I was wary of spending such a large amount on something that we didn’t much know about. My husband however was intrigued and insisted I try it,” Alice, now 66, says. She signed up and a few days later a medical team from the company visited their home to take her mouth swab samples.

After 15 days a hefty report was delivered by a doctor who patiently explained to Alice what the findings meant. “We were shocked. According to the analysis, I was severely lactose intolerant. There I was happily drinking my chai latte and milk-tea three times a day all my life. It explained many of the ailments I wrongly ascribed to gluten, and why going gluten-free didn’t improve my condition,” said Alice.

The results identified intolerances and sensitivities specific to her body which allowed her to make meaningful changes that improved her life and health. “The test was an eye-opener,” says Alice. “It also explained why my mother had suffered gastric issues—loose motions, bloating and acidity—for over 60 years of her life and no treatment beyond the temporary was able to help her heal,” she added.

The test Alice took was a DNA test, or more technically, genome sequencing, a specialized area of genomics. “We know that our bodies are made up of cells and tissues, which further contain working entities such as DNA, RNA and proteins, that collectively form our genomes,” explains genome scientist Dr Ankita Singh who heads Scientific Affairs at the Indian Cancer Genome Atlas (ICGA) Foundation. “No two genomes are similar, except for identical twins and even they may accumulate slight differences over time due to mutations or epigenetic changes,” she adds.

Dr Debojyoti Chakraborty, heading the RNA Biology Lab at the CSIR-Institute of Genomics and Integrative Biology, explained this further: “Genome sequencing essentially means that you read each alphabet that makes up your DNA. Although most of the letters in our DNA are identical, and share a common broad template, there are also a lot of person-specific changes in them, due to which someone is prone to certain diseases, or has a particular eye or hair colour.”

Genome sequencing is a complex pathway of information that goes from a person’s DNA sequence to which feature finally manifests in an individual. This has sparked advanced research into a large number of diseases such as cancer, blood diseases like sickle cell anaemia, developmental diseases such as muscular dystrophies etc.

It is now understood that to know if a disease in an individual needs to be tracked to DNA changes, sequencing is the gold standard to test this. Technological advancements have enabled scaling genetic sequencing tests for a larger consumer base.

As Dr Singh further explains, genome sequencing a patient with, say, lung cancer, identifies the patient’s genetic pattern, based on which treatment, dosage and serious side effects from medication can be better determined. “Without that crucial data, we will treat all patients in the same way. Some might respond, some might not.”

Getting Personal

For around a decade or so, commercial laboratories have started advertising and offering direct-to-consumer (DTC) genetic tests that is made available in accessible, affordable formats for people to identify probable threats to their health. This approach is a by-product of the significant rise in demand for personalised healthcare in recent years.

“Preventive healthcare is gaining traction in India because people realize that they can’t just pick a random diet off the Internet and expect it to work for them,” says Janani Thirunavukarasu, consultant nutritionist with Chennai-based personal genomics company Xcode Life Sciences. “Healthcare is a lot more personalized and that’s where we come in. We bring in personalization by looking into your genes to see what your body is designed to accept and reject, and where your body is lacking.”

Genetic testing is frequently used to check for metabolic and genetic abnormalities in newborns or to predict if would-be parents might become carriers for Down syndrome and Edwards syndrome. Another area being explored is nutrigenomics, or nutritional genomics, which studies the relationship between one’s specific genes and diet and how this interplay affects one’s health. A 2012 US study found 76 per cent of the general population believed that personalized diets based on genetic profiles would be helpful in tackling obesity and cardiovascular diseases.

Research published in Nature magazine last year established how diet and genetics impact obesity by screening 1,142 11-year-old Finnish children. The findings indicate that children who were genetically prone to obesity showed a stronger preference for unhealthy foods. Nutrigenomics sheds light on the way food and nutrition is processed by a person’s unique genetic makeup, allowing one to accurately determine how to prevent and treat certain diseases, manage weight, make informed lifestyle choices and identify intolerances or allergy triggers, as in the case of Alice.

Steps to Sequencing

Senior editor at Reader’s Digest India, Ishani Nandi sent in a sample of her own DNA to Xcode Life Sciences to try the genome analysis for the purpose of this story. “It was fascinating to me that a mere 2 ml of saliva was all it took to find out about my propensity for lactose intolerance, increased HDL cholesterol, weak joints and a host of other issues, some of which I had already discovered through painful experience, others I can now monitor and possibly offset through better informed lifestyle choices,” says the 40-year-old. “I also used to ascribe any weight gain or caffeine dependency to my own lack of willpower or failings. Learning that I have a genetic predisposition to emotional eating and am a fast metabolizer of caffeine led me to rethink the way I approach tackling these dependencies.”

Xcode Life provided Ishani reports on nutrition, sleep, skin, fitness and health, the last of which indicated her chances of being impacted by at least 45 conditions, ranging from alzheimer’s, chronic kidney disease, obstructive pulmonary diseases, Thalassemia, and epilepsy to alopecia, anxiety, depression, gout, psoriasis and arthritis. The disorders are designated as of either low, high or moderate likelihood.

“Most people are used to positive or negative test results: you either have an illness, or you don’t. But the genetic test results came in more open-ended language: ‘Likely high genetic risk for anaemia,’ remarks Ishani. “It’s easy to get alarmed.”

“A genetic analysis like this is not definitive about whether a disease will present itself or not,” explains. “The probability of a disease occurring in an individual is influenced by other factors as well. One might have a genetic change that makes them prone to having say, atherosclerosis—a condition where plaque builds up in the walls of arteries—but that is only indicative. To say that someone will have atherosclerosis, the genetic sequence of their DNA has to match with other genetic patterns,” he adds. Even environmental factors can come into play.

Guidance is Key

And this is where it becomes tricky. It is not easy to read and interpret the report without help. Dr Chakraborty stresses that it is extremely important for genetic test-takers to go through the detailed counselling. “The predictive values generally come from scientific literature and the layman is not expected to know this,” he says. “It’s not something that one can read up or Google,” he warns. An experienced genetic counsellor with the knowledge and depth of information in that field is able to explain the risk score, suggest relevant lifestyle modification, and interpret how susceptible one is to certain diseases and conditions.

Ishani was guided through every result in her reports in a one-on-one conversation with Deepika Suresh, a genomics specialist and chief of staff at Xcode Life Sciences, who identified which markers required immediate or eventual intervention as well those that she should follow up with her doctor for further investigation.

“What the test offers is a risk profile of various health conditions,” explained Suresh. “It arms you with knowledge so that you are now in a position to make choices to circumvent or preempt the condition. Family history is one way to remain vigilant, but not all genetic conditions manifest in every generation, so you may be at risk and never know. For example, your report says ‘likely high genetic risk for cardiomyopathy’—a condition no one in the last two generations of your family has identified as far as you knew. But you can now avoid it by adopting heart-healthy practices and screening for early signs of this condition. You know what to look for.”

Barriers to Scale

As of 2023, the DTC genetic testing market is valued at $1.93 billion and is expected to grow at a compound annual growth rate of 24.4 per cent from 2024 to 2030. The market is expanding rapidly and more companies are joining this space. Early proponents believed that the DTC gene tests would lead to improvements in positive health behaviours, but that has not been the case, researchers find. On the other hand, access has not led to catastrophic psychological distress as critics feared.

“I wonder why more doctors do not get their patients to do these tests; it will help decode several of our root health issues,” Alice says. She found tremendous help through her genome sequencing test, which is why she has got several of her grandchildren and relatives genome tested when they were detected to have little B12 absorption, unexplained boils and swelling on their feet, or other illnesses. “I’ll suggest every child should get gene tested at birth if possible so that their parents know what food and lifestyles are good and appropriate for them,” says Alice.

When asked if she would do the same, Ishani said, “Personally I thrive on more information, and am careful about seeking the right source before drawing conclusions or taking action about my health. However friends with whom I’ve discussed this are not all keen to do the same. Some find it unnecessary and onerous, others feel the data might elevate existing anxieties.”

Widespread acceptance among medical professionals may also take time. While Alice was thoroughly briefed by her lab counsellor on what her report says, she complains that going forward, her current physicians cannot make sense of her report and hence they do not take it seriously. Interpreting the score or probability of how one’s genes affect one’s health needs training to evaluate.

According to Dr Chakraborty, “There have been initiatives made by experienced scientists in my Institute to conduct CMEs (continuing medical education) for doctors on how to read and interpret gene sequencing panels.” He admits though that these efforts are needed on a larger scale and through medical bodies. Yet that’s a challenge in a country like India where the doctor–patient ratio is extremely skewed and doctors are hard-pressed for time.

That isn’t the only challenge however. With research in this area still in its early stages, there is as yet not enough data to understand the full social implications of empowering the public with genetic information or to develop adequate policies and regulatory measures.

Adds Suresh, “Whatever science we have, even though it’s new, it is not rudimentary or half-baked. It is established. The information is credible enough to be incorporated into practice. However, we still need regulations and standardization in place to integrate genetic testing into the health and wellness space.”

Other reasons to worry include the fact that academic research suggests that the clinical utility and validity of these tests are not yet established. Further, there are ethical, legal, and social issues that countries still need to look into. All these make it necessary for healthcare providers to step up and gain applicable knowledge. Potential consumers, for their part, need to remain vigilant.

As it stands, experts advise caution. “Genome sequencing is no joke,” exclaims Dr Singh. Both she and Dr Chakraborty suggest users start by being honest about precisely why they would want to go for genome sequencing. “One should have a clear, defined motive, especially when the results are only indicative,” says Dr Chakraborty. 

“Why add to the information overload?” asks Dr Singh. “A single test won’t provide all the answers when diagnosing a condition,” she says. Genomic testing is indeed a powerful tool to prevent and deal better with a disease, but she stresses the importance of consulting a doctor to interpret test results and suggest the next steps.

How Can Bad Genes be Fixed?

Gene editing! In 2020, Jennifer Doudna and Emmanuelle Charpentier won the Nobel Prize in Chemistry for their work on CRISPR/Cas9, a gene-editing tool that allows researchers to precisely alter the DNA of animals, plants, and microorganisms. “We do have the technology right now to take baby steps towards changing genomes. But it’s at the beginning and has a long way to go,” according to Dr Chakraborty.

Once a complete gene sequencing test indicates the pattern of the genome, and identifies its problematic, disease-causing alterations, it is possible to modify and correct these alterations and cure a disease. So far, the technology caters to only a handful of rare ailments, but these kinds of choices are gradually opening up with more research and advancement.

“In the next three to four years, we will likely have more gene sequencing at an earlier stage, which will lead us towards more gene-evidence-based solutions,” he says.

While caution about the potential excesses of a consumer-driven healthcare system is paramount, and the thin line bordering what could be done and what should be done must be navigated with care, it’s clear that the future of genomics could transform the healthcare industry in the years to come.