title: Heterogeneity testing for Alzheimer's disease within and between data sets.
abstract: We examined the three Alzheimer's disease (AD) family data sets for heterogeneity. Four markers that were represented in all three data sets were selected for analysis. Markers BCL3/EcoR-Mlu and D19S13/TaqI were chosen for chromosome 19 and D21S13/TaqI and D21S16/XbaI for chromosome 21. Homogeneity testing was performed on the data by use of Morton's pre-divided samples test (PS-test) and Smith's admixture test (A-test). The C-test of MacLean et al. [1992] was also used to test for linkage in the presence of heterogeneity. Assuming homogeneity, there was significant evidence of linkage to AD for BCL3, D19S13, D21S16 in the Duke data set and D19S13, D21S16 in the Boston data set. C-tests also provided evidence of linkage for BCL3 and D21S13 in the Duke data set, and D21S16 in the Boston data set. No evidence for heterogeneity within the data sets was found for any of the four markers using either the A-test or the C-test. For marker BCL3, PS-tests found evidence of heterogeneity between the three data sets and between early-versus late-onset families combined over all data sets.
authors.affiliation: Department of Human Genetics, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-003.
authors.forename: L L
authors.initials: LL
authors.lastname: Miller
authors.forename: L M
authors.initials: LM
authors.lastname: Ploughman
authors.forename: M L
authors.initials: ML
authors.lastname: Marazita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000453:epidemiology / Q000235:genetics*; D001900:Boston / Q000453:epidemiology; D002874:Chromosome Mapping; D002888:Chromosomes, Human, Pair 19; D002891:Chromosomes, Human, Pair 21; D005787:Gene Frequency; D008040:Genetic Linkage; D005819:Genetic Markers; D014644:Genetic Variation; D006801:Humans; D008875:Middle Aged; D009657:North Carolina / Q000453:epidemiology
chemical_list: D005819:Genetic Markers