The estimated heritability of AD is approximately 70%, and does not differ between sex.1,9 To date, 75 risk loci have been identified for AD and related dementias.8 Several studies in multiple ethnic groups have associated the APOE gene with familial-AD and sporadic late-onset AD.10 The frequency of the APOE e4 allele varies between ethnic groups; however, regardless of ethnicity, non-carriers of the APOE e4 allele are more common in controls, while carriers of the APOE e4 allele are more common in individuals with AD.10
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6.Reiman EM, Arboleda-Velasquez JF, Quiroz YT, et al; Alzheimer’s Disease Genetics Consortium. Exceptionally low likelihood of Alzheimer’s dementia in APOE2 homozygotes from a 5,000-person neuropathological study. Nat Commun 2020; 11 (1): 667.
7.Wightman DP, Jansen IE, Savage JE, et al. A genome-wide association study with 1,126,563 individuals identifies new risk loci for Alzheimer’s disease. Nat Genet 2021; 53 (9): 1276–1282.
8.Bellenguez C, Küçükali F, Jansen IE, et al. New insights into the genetic etiology of Alzheimer’s disease and related dementias. Nat Genet 2022; 54 (4): 412–436.
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