Of the five identical quintuplets born to the Dionnes in May 1934 in Toronto, Canada, only two — Anette and Cecile — are alive. The Dionnes are the first genetically documented quints who survived more than a week. The first, Emelie, died after an epileptic seizure in 1954. Marie died in 1970 from a blood clot in the brain and cancer claimed Yvonne in 2001. The lesson geneticists like Larry Gold, professor, University of Colorado and chief executive, SomaLogic, a healthcare company in the US, have learnt from the quintuplets is that health outcomes are not similar even in identical twins. They’ve also learnt that DNA is identical only at the single cell stage but not later when that cell divides. In other words, genes do not decide our destiny.

Gold, who is one of the key speakers in the conference titled “Omics meets Diseases”, to be held at the Saha Institute of Nuclear Physics (SINP), often cites the Dionne quintuplets in his talks. He does this to illustrate that the genome — the blueprint of the complete set of DNA , including all its genes — can at best indicate future risk of diseases but can’t always predict them accurately or help treat a person definitively. Many scientists like him talk about the quints to dispel myths surrounding the Human Genome Project (HGP), which decoded 25,000 genes and was completed in 2000. The $3 billion-project was expected to pave the way to precision medicine — treatment that would be tailormade for an individual based on his genetic profile as opposed to the current non-customised therapies. Doctors guess the dosage for a patient and later correct it if it doesn’t work. More than a decade has passed since HGP was completed but that promised “personalised medicine” is nowhere on the horizon. Says Gold, “Genomics is just a deep look at genetics. The hype around personalised medicine through genomics is over-reaching.”

The meet, organised jointly by SINP, the University of Calcutta, the Indian Institute of Chemical Biology and the Proteomic Society of India, will bring together researchers involved in studying human diseases using technologies beyond genomics. Now scientists are of the firm opinion that epigenomics (the study of “apparent” genetic changes without changes in one’s DNA), proteomics (the large-scale analysis of proteins) lipidomics (the study of changes in lipid profiles) or glycomics (that measures sugar compositions) are as important as genomics. Says Gold, “Genomics is largely about the risk of disease — which is very important — while other omics will be more useful for disease diagnosis and management.”

Larry Gold

Agrees Subrata Banerjee, the head of the structural genomics unit, SINP, “We need to adopt a holistic approach; all the omics complement one another. Just genomics can’t offer all the clues, because all genetic instructions do not get translated at the level of proteins (body’s basic work horses).”

This is why Abhijit Chakrabarti, biophysicist at SINP, is betting on proteomics. “Proteomics is the most promising candidate which is likely to deliver the information required for personalised medicine.”

That proteomics could hold the clue to personalised medicine was clinically shown by a Wellness Chip devised by Gold and his colleagues at SomaLogic. The chip, described in the October issue of the journal PloS One, can analyse proteins circulating in the body and pinpoint those that hold signatures of over 2,000 particular illnesses. A simple blood test can help identify the telltale proteins (called biomarkers) secreted by diseased tissues. Early identification can prevent, diagnose and even help treat the illness quickly and accurately. “We have identified biomarkers for about 30 medical conditions — such as cancer in the lungs, pancreas and ovary, mesothelioma and cardiovascular diseases — through more than 15,000 human blood samples. I will describe some of these in my lecture at the meeting,” Gold told KnowHOW. “We think our measurements will help physicians decide on the most appropriate therapy for patients. They can also watch how biomarkers shift during treatment.” This will help the doctor judge the efficacy of a drug in an individual and decide on the modalities of personalised treatment.

Many scientists, however, believe that proteomics alone won’t lead us to the El-Dorado of personalised medicine. “While it looks possible in theory, in practice there are many hurdles ahead,” admits Chakrabarti who’s been working on the proteomics of blood borne diseases like thalassaemia and leukaemia. “A script written with 20 characters in amino acids (the building blocks of proteins) has to be more complex than that written with A-T-G-C (in genes),” he adds. Gold doesn’t disagree. “The final answer will come over the next decade, and whatever ‘omic’ provides useful information will become part of medical practice,” he says. Golden words.