Molecular Complexities of Dementia: PAISA Mutations and Targeting TAF2N as Therapeutic Avenues.

Abstract

Millions of individuals worldwide are affected by Alzheimer's disease dementia (ADD) and frontotemporal dementia (FTD), with FTD characterized by degeneration of the frontal and temporal lobes leading to cognitive and behavioral impairments. A subset of Alzheimer's cases exhibits familial inheritance, with the PAISA mutation, a glutamic acid to alanine substitution at codon 280 (E280A) in the PSEN1 gene, being a primary cause of early-onset dementia. PSEN1 encodes a key component of the γ-secretase complex, which cleaves amyloid precursor protein (APP) to generate beta-amyloid (Aβ) peptides. The PAISA mutation disrupts normal Aβ processing, leading to overproduction or accumulation of Aβ, formation of amyloid plaques, and accelerated progression of dementia. Its prevalence is particularly high in Colombian families, giving rise to the term "PAISA mutation." The APOE genotype further modulates the clinical manifestation in PAISA carriers, with APOE2 potentially delaying disease onset, whereas APOE4 is associated with earlier onset. Recent research highlights TAF2N (also known as RBP56, encoded by TAF15) as a promising therapeutic target, as its modulation may regulate AD-associated genes, reduce toxic Aβ isoforms, modulate tau and APP pathways, protect neurons, and enhance synaptic function. Overall, understanding the molecular effects of PAISA mutations and exploring TAF2N-targeted therapies offers novel avenues for addressing early-onset familial AD, providing insights into broader mechanisms of disease pathogenesis.