Chen F, et al. - Using the genome-based restricted maximum likelihood method, researchers analyzed 3,568 pancreatic cancer cases and 3,363 controls of European Ancestry by deriving data from Pancreatic Cancer Case-Control Consortium genome-wide association study, to estimate overall heritability of pancreatic cancer and partition the heritability by variant frequencies and functional annotations. In this study, the estimated overall heritability was 21.2%, which was although higher as compared to previous studies but still could be downwardly biased because of the inherent limitation that these commonly used methods fail to capture heritability due to individually rare variants in a gene with a substantive overall influence on disease. The contribution of both rare and common variants to missing heritability was suggested by the estimate of pancreatic cancer heritability estimates, while exercising caution was recommended when using this approach to quantify the impact of rare variants.