Affiliations: Rhodes Center for Animal and Dairy Science, University
of Georgia, Athens, GA 30602, USA | Department of Statistics, University of Georgia,
Athens, GA 30602, USA | Institute of Bioinformatics, University of Georgia,
Athens, GA 30602, USA
Note: [] Corresponding author. Sandeep Joseph, Rhodes Center for Animal
and Dairy Science, University of Georgia, Athens, GA 30602, USA. Tel.: +1 404
578 6790; Fax: +1 706 583 0274; E-mail: [email protected]
Abstract: Gene expression profiles of 16 Alzheimer's (AD) patients, diagnosed
as incipient or healthy using Mini-Mental State Examination and Neurofibrillary
Tangles scores, were analyzed to validate the reclassification of 4 subjects
previously identified as being misdiagnosed. Three datasets were created using
original classifications (D1), new classifications, based on a
misclassification algorithm (D2), and by removing questionable subjects (D3).
Mixed model analysis was used to identify differentially expressed genes. Many
genes related to the nervous system and AD were found to be differentially
expressed in D2 and D3, while few genes, none related to NS or AD, were found
using D1. Several additional relevant genes were found when using D2 versus D3,
which were likely due to differences in sample size. These results suggest the
4 questionable subjects were likely misclassified in D1. The similarities
between results obtained using D2 and D3 provides further evidence of the
adequacy of the misclassification algorithm.
Keywords: Gene expression, Alzheimer's Disease, misclassification algorithm, mixed model analysis, Mini-Mental Sate Examination (MMSE) and Neurofibrillary Tangles
Score (NFT)
