Type : Phenotype or locus, molecular basis unknown;
Alternative titles and symbols : Alzheimer disease 6, late-onset; AD6;
Included titles and symbols : Plasma beta-amyloid-42 level quantitative trait locus;
Description : For a general phenotypic description and a discussion of genetic heterogeneity of
Alzheimer disease (AD), see 104300. Alzheimer disease (AD) is a neurodegenerative
disorder characterized by subtle onset of memory loss followed by a slowly progressive
dementia. The great majority of AD cases are of late onset (LOAD) after age 65 years.
LOAD shows complex, nonmendelian patterns of inheritance, and most likely results
from the combined effects of variation in a number of genes as well as from environmental
factors (summary by Grupe et al., 2006). The Alzheimer disease-6 (AD6) designation
refers to a susceptibility locus on chromosome 10q. Although significant associations
with several candidate genes on chromosome 10 have been reported, these findings have
not been consistently replicated, and they remain controversial (Grupe et al., 2006).;