Since glutamate and N-methyl-D-aspartate (NMDA) receptors have been implicated in several disorders of the central nervous system including stroke [20] and GRIN2A and GRIN2B genes have been recently implicated in encephalopathy with mental retardation and epilepsia [21], we sequenced the GRIN2C gene encoding the glutamate receptor, ionotropic, N-methyl D-aspartate 2 C. We also sequenced the KCNJ16 gene since KCNJ2 and KCNJ10 have been associated with mental retardation, dysmorphic syndrome and a CNS phenotype [22,23]. This evidence concerns the gene KCNJ2 and Intellectual disability.