SOHLH2 is a 425 amino acid nuclear protein that contains one basic helix-loop-helix (bHLH) domain through which it may function as a transcription factor during oogenesis and spermatogenesis. SOHLH2 exists as two alternatively spliced isoforms that are encoded by a gene which maps to human chromosome 13q13.3. Chromosome 13 houses over 400 genes, such as BRCA2 and RB1, and comprises nearly 4% of the human genome. Trisomy 13, also known as Patau syndrome, is deadly and the few who survive past one year suffer from permanent neurologic defects, difficulty eating and vulnerability to serious respiratory infections.