Intron features created from the comprehensive set of gene anntotations created on GRCh38 and mapped to GRCh37 by GENCODE (v34lift37). Intron features for each transcripts have been added to the annotation set. All other features are removed. Some annotations were obtained from GENCODE v19 when mapping failed. Scaffoldings, assenbly patches, and alternative loci are NOT included. Features include: intron.
