Why are there fewer open access TCGA mutations in DR 32 (GENCODE Update Release)?
The primary reasons for the fewer open-access mutations are from two strategies that improve quality: 1) TCGA is now using a 2-caller ensemble, instead of a single caller; 2) Removal of variants outside of the target capture region, instead of a combined “target capture + GAF exonic region”. Additionally, TCGA was the original project in which GDC open-access variants were produced and used variant rescue steps that only applied to TCGA. To keep the TCGA variant-calling pipeline consistent across projects, GDC is no longer rescuing MC3 and TCGA validation variants.