Recent studies have demonstrated that glutamate receptor δ2 gene (GRID2) is closely related to cerebellar functions in mice. This gene is predominantly located in postsynaptic dendrites of parallel fiber-Purkinje cell synapses in the cerebellum and contains potential fragile sites within large introns. These fragile sites easily develop spontaneous mutation, which leads to Purkinje cell death, contributing to the manifestation of spinocerebellar ataxia in mice. The human GRID2 shares 90% homology with the orthologous mouse gene, and therefore it has become an important candidate gene for screening the virulence gene of spinocerebellar ataxia. Dr. Chaodong Wang, Affiliated Sanming First Hospital of Fujian Medical University, China and his team screened for mutations in the coding sequence of GRID2 in 24 patients with familial or sporadic spinocerebellar ataxia and in 52 normal controls. They detected no point mutations or insertion/deletion mutations in the 16 exons of GRID2. However, a polymorphic 4 nucleotide deletion (IVS5-121_-118 GAGT) and two single nucleotide polymorphisms (c.1251G>T and IVS14-63C>G) were identified. The frequency of these polymorphisms was similar between spinocerebellar ataxia patients and normal controls. These data indicate that spontaneous mutations do not occur in GRID2 and that the incidence of spinocerebellar ataxia in humans is not associated with GRID2 mutation or polymorphisms. Related results were published in Neural Regeneration Research (Vol. 9, No. 10, 2014).
Article: " The human δ2 glutamate receptor gene is not mutated in patients with spinocerebellar ataxia," by Jinxiang Huang1, Aiyu Lin2, Haiyan Dong3, Chaodong Wang3 (1 Department of Neurosurgery, Changzheng Hospital, the Second Military Medical University, Shanghai, China; 2 Department of Neurology, The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian Province, China; 3 Department of Neurology, The Affiliated Sanming First Hospital, Fujian Medical University, Sanming, Fujian Province, China) Huang JX, Lin AY, Dong HY, Wang CD. The human δ2 glutamate receptor gene is not mutated in patients with spinocerebellar ataxia. Neural Regen Res. 2014;9(10):1068-1074.