Sex determining region Y(SRY) HMG (High mobility group) box 5 (SOX5) belongs to the family of transcription factors which is involved in early developmental stage. Sox proteins are classified into 6 subfamily groups based on their homology and SOX5 belongs to subfamily D. The group D subfamily share a conserved N terminal domain which has leucine zipper, coiled-coil domain, Glutamine rich region (Q box).Sox5 has two variants, long and short, of which, short is a part of long with N-terminal region. Short form of Sox5 is expressed in testis and long form of Sox5 (LSox5) is expressed different organs including chondrocytes and striated muscles. LSox5 and Sox6 are highly similar. In human chromosome, the gene is localized on 12p12.1.