Anterior polar cataracts are relatively uncommon, but have been described in association with mutations in EPH receptor A2 (EPHA2), alpha 8 gap junction protein (GJA8), gamma D crystallin (CRYGD), eyes absent homolog 1 (EYA1), major intrinsic protein of lens fiber (AQP0), heat shock transcription factor 4 (HSF4), and beta B1crystallin (CRYBB1). The gene discussed is PROS1; the disease is Anterior polar cataract.