Familial Risk for Alzheimer Disease in Ethnic Minorities

Abstract

E PIDEMIOLOGICAL AND molecular evidence suggests that there are multiple etiologies for Alzheimer disease (AD). Studies of the incidence and patterns of transmission in families demonstrate that relatives of affected individuals have an increased risk of developing AD compared with members of the general population. 1 With the exception of rare (probably Ͻ1%) cases harboring pathogenic mutations in the amyloid precursor protein or presenilin genes, susceptibility is governed by a complex interaction of genes and environmental factors. The most potent factor identified to date is the ⑀4 allele of apolipoprotein E conferring a relative risk of between 2.7 and 3.2 in persons having a single copy and between 12.5 and 14.9 in those homozygous for this factor. 2 Notably, these conclusions were drawn from studies of largely white populations.

When it runs in the family: putting susceptibility genes in perspective

“…Low rates of LOAD have been reported for parts of Nigeria, and the presence of an ApoE ε4 allele does not appear to be implicated when it does occur. On the other hand, ApoE ε4 is significantly associated with LOAD among African Americans, although less so than in populations of whites (Farrer, 2000). It is argued that risk reducing factors (in Africa) and risk enhancing factors (in North America) must be implicated, including other genes, their protein products, diet, and environment, but researchers also acknowledge limitations to the research methodologies used to date.…”

Emotional Health of Black and White Dementia Caregivers: A Contextual Examination

“…A S THE population continues to increase in longevity, the incidence of acquiring various diseases, such as Alzheimer's disease, is more prominent (Ferraro, 1997;Hayflick, 2000), while the overall prevalence rates of dementia appear to be higher among Black Americans than for White Americans (Heyman et al, 1991). However, racial differences may vary by type of dementia and by measurement bias that may be present due to differences in education, socioeconomic status, or other cultural dimensions (Farrer, 2000;Froehlich, Bogardus, & Inouye, 2001).…”

Living with Uncertainty: The Genetics of Late Onset Alzheimer s Disease

“…Furthermore, low rates of AD have been reported for parts of Nigeria, and the presence of an APOEε4 allele does not appear to place individuals at increased risk when it is present. On the other hand, ApoEε4 is significantly associated with dementia among African Americans, although less so than in Caucasian populations (Farrer: 2000). It is concluded that unknown risk reducing factors (in Africa) and risk enhancing factors (in North America) must be implicated, among which it is assumed are other genes, their protein products, diet, environment, and quite probably yet other factors.…”