USC researchers receive $5 million to study cancer risk across diverse populations

Scientists have long been studying the role that genes play in determining an individual’s risk for disease with a focus on individuals of European ancestry, which were easy to sample. The National Institutes of Health is now funding a consortium to look at how the data differs in diverse population segments, which has important implications when it comes to patient treatment. David Conti, PhD, and professor of preventive medicine at Keck School of Medicine of USC, and his research partners, have just been awarded $5 million.

Conti, along with Christopher Haiman, ScD, a professor of preventive medicine at Keck School of Medicine and AFLAC chair of cancer research, plan to construct and evaluate polygenic risk scores, or PRS, for cancer across a variety of racial and ethnic groups. Their goal is to provide information to the health system that could help reduce health disparity.

“The inadequate representation of diverse racial and ethnic populations limits the translational potential of genome-wide association studies findings to the world’s populations,” said Conti, who is associate director of Data Science Integration at the Norris Comprehensive Cancer Center and member of the Center for Genetic Epidemiology. “Applying PRS developed in European ancestry individuals to other populations may result in biased risk prediction, and further exacerbate health disparities due to inaccurate assessment of individuals at high risk of disease.”

Creating a large, diverse genetic cohort

The team will be creating one of the largest and most diverse genetic cohorts. They will utilize data from six large existing cohorts that include over 300,000 individuals, 100,000 non-European individuals and represent 24,000 non-European cancer cases. In addition to those of European heritage, cohort subjects are from African, Asian, and Hispanic populations.

Researchers have found that certain racial and ethnic groups have much higher incidence rates of certain types of cancer. Black men, for example, have an approximately 67% higher incidence rate of prostate cancer than their European-heritage counterparts. Interplay of an individual’s genes that results in a predisposition to a disease is suspected to be the cause, however most genome studies have neglected to include diverse participants.

By developing statistical and machine learning approaches and applying them to a wide range of cohorts, Conti and his team hope to produce insights that can help guide physicians and public health screening.

“Ultimately, constructing and evaluating risk models in non-European ancestry populations is essential to broaden the impact of genomic medicine on human health,” Conti said.

The recent grants from NIH have been awarded to investigators of varied scope, and the consortium will bring the researchers together using a cloud-based lab and resource system.

Other investigators are John Witte, PhD, MS, of University of California San Francisco, and Pete Kraft, PhD, of Harvard University. The grant includes $3 million direct costs and $5 million total over a five-year period from 6/1/21 to 5/31/26.

Cohorts involved in the project are the Multiethnic Cohort (MEC); the Kaiser Resource for Genetic Epidemiology Research on Aging (GERA) cohort; the Women’s Health Initiative (WHI); the Harvard Nurses Health Studies (NHS); the Harvard Health Professionals Follow-Up Study (HPFS); and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO).