Discovery of a Missense Mutation (Q222K) of the APOE Gene from the Australian Imaging, Biomarker and Lifestyle Study.

After age, polymorphisms of the Apolipoprotein E () gene are the biggest risk factor for the development of Alzheimer's disease (AD). During our investigation to discovery biomarkers in plasma, using 2D gel electrophoresis, we found an individual with and unusual apoE isoelectric point compared to 2, 3, and 4 carriers. Whole exome sequencing of from the donor confirmed a single nucleotide polymorphism (SNP) in exon 4, translating to a rare Q222K missense mutation. The apoE 4 (Q222K) mutation did not form dimers or complexes observed for apoE 2 & 3 proteins.