The study, published July 23 in Nature, offers a potential breakthrough in solving one of modern-day oncology’s most frustrating mysteries: why checkpoint inhibitors work for some patients but not others — and how we can extend their benefits to more people. 

Genome assemblies from 65 individuals, representing a variety of the world’s populations, are advancing the scientific exploration of complex genetic structural variation. Structural variations are genetic code alterations that span more than 50 base pairs, the rungs on the DNA ladder. These changes were hard to detect until the recent advent of newer sequencing technologies and analytical algorithms, as well as larger collections of more complete, diverse human genomes. After identifying such variation between and within populations, it may be easier to determine if the differences result in disease or other traits, like helping our ancestors adapt to their environments.