A groundbreaking study led by a team of researchers at Yale’s Department of Surgery sheds light on a significant genomic phenomenon that could help explain racial disparities in cancer outcomes. The Nature journal study, authored by Leanne Brown, a general surgery resident, and principal investigator Jason Sheltzer, Ph.D., examines over 1,800 cancer samples from self-reported Black patients in the United States and reveals that tumors in Black individuals are more likely to exhibit whole-genome duplications (WGDs) compared to those from white patients.
WGDs are a type of genomic alteration that involves the complete duplication of an organism’s genome. This event can result in increased metastasis, more aggressive disease progression, and poorer patient prognosis. The study found that this increased rate of WGDs was consistent across various cancer types, including breast, endometrial, and lung cancers, and was linked to shorter survival rates for Black patients.
Furthermore, the study explored environmental factors, showing that exposure to combustion byproducts, such as those found in pollution and tobacco smoke, could induce WGDs in cultured cells. Tumors from Black patients exhibited mutational signatures suggesting that these environmental carcinogens may contribute to the higher frequency of WGDs seen in their cancers.
These findings not only identify a new genomic factor associated with cancer progression but also underscore the potential role of environmental factors in racial disparities in cancer outcomes. By highlighting the link between WGDs and environmental exposures, the research opens avenues for further studies on how these factors may influence cancer biology and patient survival, particularly for historically underserved populations. This work represents a critical step in understanding the complex interplay between genetics, environmental exposures, and health disparities.