Serum glutamine synthetase has no value as a diagnostic biomarker for alzheimer's disease

In order to test whether serum glutamine synthetase (GS) is of potential diagnostic value for Alzheimer's disease (AD), we set up a study to compare serum GS concentrations between AD patients and control subjects. The study population (n = 165) consisted of AD patients (n = 94) and age-matched (n = 41) and ageunmatched (n = 30) control subjects. Serum GS analysis was performed by means of ELISA. No significant differences in serum GS levels were found between the ADgroup and age-matched controls. Age correlated positively with serum GS concentrations in AD patients and control subjects. This study suggests that serum GS levels have no diagnostic value for AD