Familial Alzheimer's disease (FAD) has been shown to be genetically heterogeneous, with a
very small proportion of early onset pedigrees being associated with mutations in the
amyloid precursor protein (APP) gene on chromosome 21, and some late onset pedigrees
showing associations with markers on chromosome 19. We now provide evidence for a
major early onset FAD locus on the long arm of chromosome 14 near the markers D14S43
and D14S53 (multipoint lod score ẑ= 23.4) and suggest that the inheritance of FAD may be …

Alzheimer disease (AD) is a common, fatal, degenerative disease of the adult human central
nervous system associated with distinctive neuro-pathological features and with progressive
cognitive and intellectual decline during mid-to late adult life (Kätzman, 1986). In some
families AD is inherited as an autosomal dominant trait (St. George-Hyslop et al., 1989),
subsequent studies have revealed that the disorder is genetically heterogeneous (St.
George-Hyslop et al., 1991). Thus, a small proportion of FAD cases are associated with …