Together with the exonic variants c.837C>A (p.Asn279Lys, N279K) and c.902C>T (p.Pro301Leu, P301L), c.1920+16C>T is among the most frequently reported MAPT mutations, associated with a wide clinical spectrum including bvFTD, PSP-like, and occasionally AD-like presentations. The gene discussed is MAPT; the disease is Alzheimer disease.