STMN2 and amyotrophic lateral sclerosis: STMN2, a neuronal protein that regulates microtubule stability, contains a cryptic exon 2a (CE2a) that is normally excluded from mature STMN2 mRNA.[8, 9, 10] However, TDP‐43 depletion or functional impairment results in CE2a inclusion, introducing a premature stop codon and a polyadenylation signal, leading to a significant reduction in STMN2 mRNA levels.[9] Similarly, UNC13A, a high‐risk gene for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), harbors a cryptic exon between exons 20 and 21.