NUDT19 (nudix (nucleoside diphosphate linked moiety X)-type motif 19), also known as RP2, is a 375 amino acid protein and coenzyme A diphosphatase that assists in the hydrolysis of CoA esters. A member of the nudix hydrolase family, NUDT19 contains one nudix hydrolase domain and localizes to both mitochondria and peroxisome. NUDT19 utilizes magnesium and/or manganese as cofactors and is encoded by a gene that maps to human chromosome 19q13.11. Chromosome 19 consists of over 63 million bases, houses approximately 1,400 genes and is recognized for having the greatest gene density of the human chromosomes. It is the genetic home for a number of immunoglobulin (Ig) superfamily members, including the killer cell and leukocyte Ig-like receptors, a number of ICAMs, the CEACAM and PSG familes and Fc receptors (FcRs).