ALLELIC ASSOCIATION AT THE D14S43 LOCUS IN EARLY-ONSET ALZHEIMERS-DISEASE

The D14S43 marker is closely linked to the major gene for early onset autosomal dominant Alzheimer's disease on chromosome 14, Allelic frequ encies at the D14S43 locus were compared in 113 familial and isolated cases of early onset Alzheimer's disease (<60 years of age at onset) ( EOAD) and 109 unaffected individuals of the same geographic origin. Al lele 7 was significantly (P = 0.033) more frequent in type 1 EOAD pati ents (13.2%), defined by the presence of at least another first degree relative with EOAD, than in controls (4.1%). Since an autosomal domin ant gene is probably responsible for type 1 patients, allelic associat ion may reflect linkage disequilibrium at the D14S43 locus. This would mean that some patients share a common ancestral mutation. However, s ince multiple tests were carried out, this result must be interpreted with caution, and needs confirmation in an independent sample. (C) 199 5 Wiley-Liss, Inc.