AMPA receptors (AMPARs) are tetrameric ligand-gated channels made up of combinations of GluA1-4 subunits encoded by GRIA1-4 genes. GluA2 has an especially important role because, following post-transcriptional editing at the Q607 site, it renders heteromultimeric AMPARs Ca2+-impermeable, with a linear relationship between current and trans-membrane voltage. Here, we report heterozygous de novo GRIA2 mutations in 28 unrelated patients with intellectual disability (ID) and neurodevelopmental abnormalities including autism spectrum disorder (ASD), Rett syndrome-like features, and seizures or developmental epileptic encephalopathy (DEE). In functional expression studies, mutations lead to a decrease in agonist-evoked current mediated by mutant subunits compared to wild-type channels. When GluA2 subunits are co-expressed with GluA1, most GRIA2 mutations cause a decreased current amplitude and some also affect voltage rectification. Our results show that de-novo variants in GRIA2 can cause neurodevelopmental disorders, complementing evidence that other genetic causes of ID, ASD and DEE also disrupt glutamatergic synaptic transmission.

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Despite the growing demand of tourism in Malaysia, there are no resolute efforts to develop beaches as tourist destinations. With no incentives to monitor public beaches or to use them in a sustainable manner, they might eventually degenerate in quality as a result of influx of pollutants. This calls for concerted action plans with a view to promoting their sustainable use. The success of such plans is inevitably anchored on the availability of robust quality monitoring schemes. Although significant efforts have been channelled to collation and public disclosure of bacteriological quality data of rivers, beach water monitoring appears left out. This partly explains the dearth of published information related to beach water quality data. As part of an on-going nation-wide surveillance study on the bacteriological quality of recreational beaches, this paper draws on a situation analysis with a view to proffering recommendations that could be adapted for ensuring better beach water quality in Malaysia.