{"id":"doi:10.1038/s43856-026-01921-y","kind":"article","title":"Phosphorylated tau 217 in young adults with Down syndrome and Down syndrome regression disorder","authors":["Santoro JD","Abdel-Latif S","Banerjee AK","Mager H","Silverman M","Kazerooni L","Otey ST","Yousuf MM","Lucas MC","Schlachetzki Z","Rissman RA","Rafii MS"],"author_count":12,"year":2026,"published":"2026-09-21","venue":"Communications medicine","cited_by":0,"doi":"10.1038/s43856-026-01921-y","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1038/s43856-026-01921-y","archive_url":"https://space-kitty.com/papers/doi:10.1038/s43856-026-01921-y","updated":null,"pmid":"42897209","pmcid":"PMC13680608","openalex_id":null,"pdf_url":"https://europepmc.org/articles/PMC13680608/pdf","abstract":"Background Down syndrome regression disorder (DSRD) causes a rapid loss of cognitive, behavioral, and daily living skills, usually in adolescents and young adults with Down syndrome. Because people with Down syndrome have a high lifetime risk of Alzheimer's disease, we examined whether DSRD is associated with an Alzheimer-related pattern of tau pathology. Methods In this prospective, single-center study, we measured plasma phosphorylated tau-217 (p-tau217), a blood marker of Alzheimer pathology, in 132 participants: 48 with DSRD, 39 with Down syndrome without regression (DSwR), and 45 neurodevelopmental controls. We compared p-tau217 concentrations across groups and examined relationships with demographic factors, medical conditions, treatment status, and diagnostic test abnormalities. Results Median p-tau217 concentrations were similar in the DSRD (0.082 pg/mL), DSwR (0.084 pg/mL), and neurodevelopmental control (0.080 pg/mL) groups (overall comparison, p = 0.57). Pairwise comparisons and models accounting for demographic and clinical factors also showed no statistically significant group differences. Among participants with DSRD, p-tau217 was not associated with treatment status or abnormalities on brain-wave testing, neuroimaging, or cerebrospinal fluid analysis. No clinical or demographic factor remained associated with p-tau217 after accounting for the number of analyses performed. Conclusions These findings provide no evidence of a group-level Alzheimer-related p-tau217 elevation in young people with DSRD and support DSRD as a condition distinct from Alzheimer's disease. However, a single blood measurement cannot exclude Alzheimer pathology in an individual. Longitudinal studies using several complementary biomarkers are needed.","abstract_license":"CC-BY (article license as recorded by Europe PMC; abstract reproduced unmodified apart from markup removal)","license":"CC-BY","is_open_access":true,"peer_reviewed":null,"categories":[],"details":null,"provenance":"europepmc","attribution":"Abstract of \"Phosphorylated tau 217 in young adults with Down syndrome and Down syndrome regression disorder\" by Santoro JD, Abdel-Latif S, Banerjee AK et al., https://doi.org/10.1038/s43856-026-01921-y, used under its Creative Commons Attribution license (CC-BY); markup removed, otherwise unmodified.","topics":[{"slug":"neurodegeneration","name":"Alzheimer's, Parkinson's & Neurodegeneration","domain_slug":"medicine"}],"cited_in_dossiers":[]}