Chinese people have higher risk of hereditary Lynch syndrome and cancer

Image credits: Photo by Zeng Kunshun, taken from Lianhe Zaobao.

Singapore’s genomic research has found that Lynch syndrome, an inherited condition that significantly increases cancer risk, affects about 1 in 530 people locally, with a higher prevalence among Chinese individuals at about 1 in 420. The condition has no direct symptoms and can only be diagnosed through genetic testing.

Data from Singapore’s National Precision Medicine (NPM) programme, which analysed the genomes of 10,000 Singaporeans, showed that Chinese individuals are more likely to carry Lynch syndrome-related genetic variants and face substantially higher cancer risks. For example, while the general population has about a 5% lifetime risk of colorectal cancer, the risk can rise to 61% for Lynch syndrome carriers. For women, the risk of uterine cancer increases from about 3% in the general population to as high as 54%.

Ms Li Shao-Tzu, Principal Genetic Counsellor at the Cancer Genetics Service, National Cancer Centre Singapore, shared that genetic testing for Lynch syndrome is like deciding whether to switch on the headlights while driving at night. Some people prefer not to know what lies ahead until they encounter a problem, while others would rather illuminate the road to identify potential obstacles. Although testing cannot eliminate genetic risks, it can help individuals anticipate them, take preventive measures, and reduce the likelihood of serious consequences through earlier surveillance and intervention. However, she noted that learning about elevated genetic risks can also create emotional and psychological challenges.

Subsidies are already available for certain inherited conditions, including familial hypercholesterolemia and, from December, hereditary breast and ovarian cancer testing for higher-risk groups. MOH said it will continue evaluating the clinical and cost-effectiveness of extending subsidies to other hereditary conditions, including Lynch syndrome. 

Looking ahead, the NPM programme has entered its third phase and aims to recruit at least 400,000 participants over the next five years for genome sequencing. The goal is to better understand population health and disease risk factors, with findings ultimately being translated into routine clinical care and preventive healthcare for Singapore’s population.