Table 1.

Candidate genes implicated in ASD.

Gene	Protein	SFARI Gene Score	Evidence	References
SLC1A2	excitatory amino acid transporter 2 (EAAT2)	Syndromic (Score 3)	-Rare de novo deletion, Genetic Association	[153]
GRIA2	Glutamate ionotropic receptor AMPA type subunit 2	High confidence (Score 1)	-Heterozygous de novo variants;-19 megabase deletion in the chromosomal region containing the gene	[119,120,125,126,154]
GRIN2B	Glutamate Ionotropic Receptor NMDA Type Subunit 2B	High confidence (Score 1)	-Rare missense mutations; -de novo splice-site variants -de novo loss-of-function variants	[127,128,129,130,131,132,133,134]
GRIA1	Glutamate Ionotropic Receptor AMPA Type Subunit 1	Strong candidate (Score 2)	-Missense variant (p.Ala636Thr)	[121,135,136]
GRIN2A	Glutamate Ionotropic Receptor NMDA Type Subunit 2A	Strong candidate (Score 2)	-Rare pathogenic deletions -Heterozygous de novo missense variant	[123,137,138,139,140,141,142,143,144,145]
GRIK2	Glutamate ionotropic receptor kainate type subunit 2	Strong candidate (Score 2)	-Rare Single Gene Mutation, Genetic Association	[21,146]
GRIK5	Glutamate ionotropic receptor kainate type subunit 5	Strong candidate (Score 2)	-Rare single gene mutations	[147,148]
GRIP1	Glutamate Receptor-Interacting Protein 1	Strong candidate (Score 2)	-Missense mutations	[149]
GRID1	Glutamate Ionotropic Receptor Delta Type Subunit 1	Strong candidate (Score 2)	-Rare Single Gene Mutation, Genetic Association	[150,151]
GRM5	Glutamate metabotropic receptor 5	Suggestive evidence (Score 3)	-De novo in-frame deletion variant, Genetic Association; -Twelve rare variants	[155,156]
GRM7	Glutamate metabotropic receptor 7	Suggestive evidence (Score 3)	gene variations and susceptibility to ASD; Rare de novo deletion	[157,158]
GRM8	Glutamate metabotropic receptor 8	/	-Variants in the chromosomal region 7q21–32 -Microdeletion in the chromosomal region 7q31.33q32.1	[20,152]