Next, the light and electron microscopic analysis of AD-like pathology in 3xTg mice included the detection of epitopes for abnormally altered tau, and revealed intraneuronal immunoreactivity, for instance, for Alz50, MC1, AT8, and PHF-1 at already 3 weeks of age, whereas straight filaments appeared only in 23 month-old female mice [51]. The gene discussed is MAPT; the disease is Alzheimer disease.