The genome specifies all proteins in a cell. It has long been assumed that genetic information is faithfully passed on from DNA to RNA; a recent groundbreaking discovery (Science, 2011, 1207018), however, identifies widespread differences between DNA sequences and corresponding RNA transcripts (RDD) in human cells, and many RDDs generate proteins that do not precisely match their genes. The identified RDDs are prevalent: about 40% of human genes have at least one RDD. Widespread RDDs represent a totally unexplored area of human genome variation, and future disease association studies may need to consider not only DNA variants, but also RNA variants, which can be related to disease susceptibility and manifestations.
The database of RNA-DNA differences (DRDD) contains currently available RDD data. Users can examine their genes of interest by searching for genes using ID, function, name and gene ontology. Users can also Blast their gene sequences against DRDD or browse and download the whole database. The identified human RDDs are likely only the tip of the iceberg. More RDDs in other tissues and species are expected and will be timely incorporated into DRDD.