This group also published results showing that 18F-FDDNP tracer uptake reflects neuropathology in brain regions most affected by repetitive head trauma (84); that 18F-FDDNP detects in vivo tau and amyloid brain signals in military personnel with mild TBI similar to those seen in retired football players but distinct from AD (85); and that 18F-FDDNP PET findings in a retired player correlated with postmortem tau deposition, supporting its diagnostic potential (86). The gene discussed is MAPT; the disease is Alzheimer disease.