Mumbai News: Landmark Tata Memorial Study Finds Genes That Cause Oral Cancer 10 Years Earlier In High-Risk Tobacco Chewers

Mumbai, Nov 29: A landmark Genome-Wide Association Study (GWAS) by the Centre for Cancer Epidemiology at ACTREC, Tata Memorial Centre, has identified key genetic factors that explain why some tobacco chewers in India develop oral cancer almost 10 years earlier than others.

The findings, published in eBioMedicine (The Lancet Discovery Science), highlight specific genetic markers that sharply increase susceptibility to buccal mucosa cancer, one of India’s most common and preventable cancers.

Buccal mucosa cancer is a type of oral cancer that develops in the inner lining of the cheeks and is often linked to tobacco use, alcohol consumption, and poor oral hygiene.

Study Analyses Over 4,400 Individuals to Identify High-Risk Genes

The study analysed 2,160 cancer patients and 2,325 healthy individuals from across India, scanning their genomes to understand genetic risks. Researchers identified important genetic risk regions on chromosomes 5 and 6 near genes such as CLPTM1L-TERT, HLA-DRB1, HLA-DQB1, and CEP43, while a global meta-analysis revealed additional markers near NOTCH1. Altogether, six key genes were found to influence cancer risk.

Using this data, scientists calculated a polygenic risk score and found that tobacco chewers with high genetic susceptibility developed oral cancer a decade earlier than those with low genetic risk. India records about 141,342 oral cancer cases every year, and rates in some states reach up to 33 per 100,000 people.

Experts Call It First Strong Genetic Evidence Behind Early Oral Cancer

Experts say the study provides the first strong genetic explanation for why oral cancer affects some people earlier despite similar lifestyle habits. Dr. Sudeep Gupta, Director of Tata Memorial Centre, said the research shows the need to study gene–environment interactions in India. He reiterated that tobacco chewing remains the single most preventable cause, responsible for over 80% of oral cancers.

Dr. Pankaj Chaturvedi, Director of ACTREC, noted that tobacco chewers face 26 times higher risk of oral cancer than non-users, and those with high genetic risk have double the susceptibility compared to those with low genetic risk. International experts, including Dr. Elisabete Weiderpass of WHO’s cancer agency, hailed the study as a major step forward in understanding the combined impact of genetics and tobacco exposure.

Genetic Predisposition Can Improve Early Detection and Prevention

Dr. Rajesh Dikshit, Director of CCE, said that understanding genetic predisposition can improve prediction, early detection, and prevention. The study also pointed to the role of immune pathways and nicotine receptor-related genes in cancer development.

“Tobacco is the strongest risk factor, but our study shows a clear genetic component as well,” said Dr. Sharayu Mhatre, lead author of the study. “Tobacco chewers with a high genetic risk score show about 24% more oral cancer cases, underscoring the need for Indian-specific genetic data.”

Oral Cancer Continues to Be a Major Public Health Burden in India

Oral cancer remains a major public health challenge in India, which accounts for nearly one-third of global cases. High use of smokeless tobacco, betel quid, and areca nut continues to fuel the disease burden. While genetic susceptibility increases risk, experts stress that avoiding tobacco, alcohol, and areca nut remains the most effective way to prevent oral cancer.

Role of genetic susceptibility

Genetic susceptibility means that certain inherited gene variations can make a person more likely to develop a disease, though it does not guarantee that they will. In oral cancer, some people carry genetic differences that reduce the body’s ability to repair DNA damage, increase sensitivity to harmful chemicals from tobacco, alcohol, and areca nut, or affect immune and inflammation pathways.

These variations do not directly cause cancer but raise the risk—especially when combined with lifestyle factors like tobacco use—explaining why not everyone exposed to the same risks develops the disease.

Major exposure studied:
Bidi smoking, gutkha chewing, betel quid with tobacco, tobacco quid, khaini, mawa, mishri, second-hand smoke

Risk of cancer (in case of taking only one form of tobacco):
Gutkha – 33.7%
Betel quid + tobacco – 14.8%
Tobacco quid – 24.2%
Khaini – 5.3%
Second-hand smoke – 1.3%

Top cities with mouth cancer in males (percent):
Ahmedabad – 20.7
Bhopal – 17.4
Kamrup Urban District – 13.4
Aurangabad – 12.6
New Delhi – 10.5
Mumbai – 10.3

Also Watch:

Top cities with mouth cancer in females (percent):
Meghalaya – 9.7
Kamrup Urban District – 6.9
Bangalore – 6.9
Mumbai – 4
Bhopal – 4
Ahmedabad – 3.9

To get details on exclusive and budget-friendly property deals in Mumbai & surrounding regions, do visit: https://budgetproperties.in/