ZC3H13 is a 1668 amino acid protein that contains one C3H1-type zinc finger. ZC3H13 is phosphorylated upon DNA damage, most likely by ATM or ATR. Two isoforms of ZC3H13 exists as a result of alternative splicing events. The gene encoding ZC3H13 maps to chromosome 13, which contains around 114 million base pairs and 400 genes. Key tumor suppressor genes on chromosome 13 include the breast cancer susceptibility gene, BRCA2, and the RB1 (retinoblastoma) gene. As with most chromosomes, polysomy of part or all of chromosome 13 is deleterious to development and decreases the odds of survival. Trisomy 13, also known as Patau syndrome, is quite deadly and the few who survive past one year suffer from permanent neurologic defects, difficulty eating and vulnerability to serious respiratory infections.