NfL, a major constituent of axons, demonstrates a non-specific increase in response to brain injury or damage and correlates with neuroinflammation.8 GFAP, associated with astrogliosis, is linked to pathological processes in Alzheimer’s disease, particularly amyloid build-up, and neuroinflammation.9 The complexity and heterogeneity of neurodegenerative diseases complicate outcome prediction and patient care. The gene discussed is GFAP; the disease is early-onset autosomal dominant Alzheimer disease.