PROB1 (Proline Rich Basic Protein 1) is located on human chromosome 5q31.2. The PROB1 gene is 3251 bp long and contains a single exon. PROB1 is composed of 1015 amino acids. Structurally, the encoded protein is reported to be 106917 Da in mass. It contains two proline-rich regions, which compose the majority of the protein, and a domain of unknown function (DUF). The PROB1 (also known as C5orf65) gene is conserved in chimpanzee, Rhesus monkey, dog, cow, mouse, and rat. 141 organisms have orthologs with human gene PROB1. PROB1 is associated with some diseases, such as Keratoconus.