Deep and Frequent Phenotyping for Early Alzheimer’s Research

Deep and Frequent Phenotyping is a University of Oxford research project on preclinical and very early Alzheimer’s disease, the stage before memory symptoms are established. His records list Dr. Costilla Reyes’s participation from September 2016 to May 2018. A phenotype is a person’s measurable characteristics, and a biomarker is a measurement that reflects a biological process; “deep and frequent” refers to taking many different measures and repeating them often, so that small changes over time can be followed.

The project combined established markers, including PET amyloid imaging and structural MRI, with emerging measures such as PET tau imaging and retinal imaging. PET (positron emission tomography) uses a radioactive tracer to show where proteins such as amyloid and tau accumulate in the brain, and MRI (magnetic resonance imaging) shows brain structure. The project also considered electrophysiology and peripheral molecular markers as further candidate measures for this population.

Its aim was to evaluate these measures alone and together with conventional assessments of clinical and cognitive change, as a step toward a multimodal marker set for measuring change in Alzheimer’s disease. Such measures matter for experimental medicine, in which small, carefully measured studies test whether a biological signal is reliable enough to guide later clinical trials.

The project examined whether very frequent phenotyping could be carried out in practice, be welcomed by participants, and be supported by protocols, governance, and processes ready for clinical trials within a reasonable timeframe and cost. Measures that can be repeated often and across several modalities make it possible to follow change in smaller groups over shorter periods, which is what experimental medicine needs in order to evaluate new approaches to Alzheimer’s disease earlier in its course.