Chen, ChiungMei, Hou, YiTing, Liu, JuYun, Wu, YihRu, Lin, ChihHsin, Fung, HonChung, Hsu, WenChuin, Hsu, Yuying, Lee, ShenHung, HsiehLi, HsiuMei, Su, MingTsan, Chen, ShuiTein, Lane, HsienYuan, and LeeChen, GueyJen
PPP2R2B, a protein widely expressed in neurons throughout the brain, regulates the protein phosphatase 2A PP2A activity for the microtubuleassociated protein tau and other substrates. Altered PP2A activity has been implicated in spinocerebellar ataxia 12, Alzheimers disease AD, and other tauopathies. Through a casecontrol study and a reporter assay, we investigated the association of PPP2R2BCAG repeat polymorphism with Taiwanese AD, essential tremor ET, Parkinsons disease PD, and schizophrenia and clarified the functional implication of this polymorphism. The distribution of the alleles was not significantly different between patients and controls, with 68.6–76.1 alleles at lengths of 10, 13, and 16 triplets. No expanded alleles were detected in either group. However, the frequency of the individuals carrying the short 5, 6, and 7triplet alleles was notably higher in patients with AD 5180 2.8, Fishers exact test, P 0.003; including 2 homozygotes and ET 4132 3.0, Fishers exact test, P < 0.001 than in the controls 1625 0.2. The PPP2R2Btranscriptional activity was significantly lower in the luciferase reporter constructs containing the CAG5–7allele than in those containing the common 10, 13, and 16triplet alleles in both neuroblastoma and embryonic kidney cells. Therefore, our preliminary results suggest that the PPP2R2Bgene CAG repeat polymorphism may be functional and may, in part, play a role in conferring susceptibility to AD and ET in Taiwan. © 2008 WileyLiss, Inc.