Genetic association between alpha-2 macroglobulin and Japanese sporadic Alzheimer's disease

Alpha-2 macroglobulin (encoded by the gene A2M) is a serum pan-protease inh ibitor that may be related with the pathogenesis of Alzheimer's disease (AD ) because of its ability to mediate amyloid beta degradation. Recently, sev eral groups have reported that the five-nucleotides deletion in A2M gene at the 5' splice site of exon 18 might increase risk for AD. In the present s tudy, therefore, this mutation was studied in 69 healthy controls and 55 sp oradic AD cases by polymerase chain reaction- restriction fragment length p olymorphism method. The allelic frequencies with the deletion (A2M-2) are 9 .4 and 6.4% in the control and AD groups, respectively. There is no signifi cant difference in the A2M-2 frequencies between the controls and sporadic AD cases. This is the first report to study the frequencies of A2M-2 in Jap anese AD cases, suggesting its no genetic association with sporadic AD. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.