A haptoglobin (HP) structural variant alters the effect of APOE alleles on Alzheimer's disease.

TitleA haptoglobin (HP) structural variant alters the effect of APOE alleles on Alzheimer's disease.
Publication TypeJournal Article
Year of Publication2023
AuthorsBai H, Naj AC, Benchek P, Dumitrescu L, Hohman T, Hamilton-Nelson K, Kallianpur AR, Griswold AJ, Vardarajan B, Martin ER, Beecham GW, Below JE, Schellenberg G, Mayeux R, Farrer L, Pericak-Vance MA, Haines JL, Bush WS
Corporate AuthorsAlzheimer's Disease Genetics Consortium
JournalAlzheimers Dement
Date Published04/2023
ISSN1552-5279
Abstract

BACKGROUND: Haptoglobin (HP) is an antioxidant of apolipoprotein E (APOE), and previous reports have shown HP binds with APOE and amyloid beta (Aβ) to aid its clearance. A common structural variant of the HP gene distinguishes it into two alleles: HP1 and HP2.

METHODS: HP genotypes were imputed in 29 cohorts from the Alzheimer's Disease Genetics Consortium (N = 20,512). Associations between the HP polymorphism and Alzheimer's disease (AD) risk and age of onset through APOE interactions were investigated using regression models.

RESULTS: The HP polymorphism significantly impacts AD risk in European-descent individuals (and in meta-analysis with African-descent individuals) by modifying both the protective effect of APOE ε2 and the detrimental effect of APOE ε4. The effect is particularly significant among APOE ε4 carriers.

DISCUSSION: The effect modification of APOE by HP suggests adjustment and/or stratification by HP genotype is warranted when APOE risk is considered. Our findings also provided directions for further investigations on potential mechanisms behind this association.
DOI10.1002/alz.13050
Alternate JournalAlzheimers Dement
PubMed ID37051669