Whittock and Bower (2003) identified and characterized, at the genetic level, a novel human desmoglein cDNA sharing homology with desmoglein-1 (DSG1), -2 (DSG2), and -3 (DSG3) and named it desmoglein-4 (DSG4). The 3.6-kb human DSG4
cDNA contains an open reading frame of 3,120 bp that encodes a precursor protein of 1,040 amino acids. The predicted mature protein comprises 991 amino acids with a molecular mass of 107,822 Da at pI 4.38. The human DSG4 protein shares 41%, 37%, and 50% sequence identity with human DSG1, DSG2, and DSG3, respectively. Using RT-PCR on multiple tissue cDNA samples, Whittock and Bower (2003) demonstrated that DSG4 has very specific tissue expression in salivary gland, testis, prostate, and skin.