CLDND2 (claudin domain containing 2) is a 167 amino acid multi-pass membrane protein that belongs to the PMP-22/EMP/MP20 family and is encoded by a gene that maps to human chromosome 19q13.33. Consisting of around 63 million bases with over 1,400 genes, chromosome 19 makes up over 2 % of human genomic DNA. Chromosome 19 includes a diversity of interesting genes and is recognized for having the greatest gene density of the human chromosomes. It is the genetic home for a number of immunoglobulin superfamily members including the killer cell and leukocyte Ig-like receptors, a number of ICAMs, the CEACAM and PSG family, and Fc receptors. Key genes for eye color and hair color also map to chromosome 19. Peutz-Jeghers syndrome, spinocerebellar ataxia type 6, the stroke disorder CADASIL, hypercholesterolemia and insulin-dependent diabetes have been linked to chromosome 19.