| Gene |
Chromosome |
Location |
Syndrome |
Category |
| G6PC | 17 | q21.31 | Glycogen storage disease type I | Hyperlipidemia | |
| G6PD | 23 | q28 | Glucose-6-phosphate dehydrogenase deficiency | Tachycardia (>100 beats/minute) | |
| GABRA1 | 5 | q34 | Juvenile myoclonic epilepsy | Epilepsy and seizures | |
| GABRA5 | 15 | q12 | GAMMA-AMINOBUTYRIC ACID RECEPTOR ALPHA-5 | Autism spectrum | |
| GABRB3 | 15 | q12 | Epilepsy childhood absence 5 (ECA5) | Autism spectrum | |
| GABRD | 1 | p36.33 | Genetic epilepsy with febrile seizures plus | Ataxia spectrum | |
| GABRD | 1 | p36.33 | Genetic epilepsy with febrile seizures plus | Epilepsy and seizures | |
| GABRG2 | 5 | q34 | Genetic epilepsy with febrile seizures plus | Ataxia spectrum | |
| GABRG2 | 5 | q34 | Genetic epilepsy with febrile seizures plus | Epilepsy and seizures | |
| GABRG3 | 15 | q12 | GAMMA-AMINOBUTYRIC ACID RECEPTOR GAMMA-3 | Autism spectrum | |
| GAD1 | 2 | q31 | Cerebral palsy spastic quadriplegic type 1 (CPSQ1) disorder | Cerebral palsy | |
| GADEVS | 14 | q32.2 | GABRIELE-DE VRIES SYNDROME | Autism spectrum | |
| GALE | 1 | p36.11 | Galactosemia (type III) | Galactosemia | |
| GALK1 | 17 | q25.1 | Galactosemia (type II) | Galactosemia | |
| GALT | 9 | p13.3 | Galactosemia (type I) | Galactosemia | |
| GAMT | 19 | p13.3 | Guanidinoacetate methyltransferase deficiency | Autism spectrum | |
| GAN | 16 | q23.2 | Giant axonal neuropathy | Ataxia spectrum | |
| GATA3 | 10 | p14 | Rheumatoid arthritis | Arthritis | |
| GATA4 | 8 | p23.1 | heterotaxy syndrome | Heterotaxy | |
| GATM | 15 | q21.1 | Arginine glycine amidinotransferase deficiency | Autism spectrum | |
| GBA | 1 | q22 | Parkinson disease - other | Parkinsonism | |
| GBE1 | 3 | p12.3 | Glycogen storage disease type IV (GSD IV) | Arthrogryposis spectrum | |
| GCGR | 17 | q25.3 | Type 2 Diabetes | Diabetes | |
| GCK | 7 | p13 | Permanent neonatal diabetes mellitus | Diabetes | |
| GCK | 7 | p13 | Gestational diabetes | Diabetes | |
| GCK | 7 | p13 | Congenital hyperinsulinism | Diabetes | |
| GCKR | 2 | p23.3 | Type 2 Diabetes | Diabetes | |
| GCKR | 2 | p23.3 | Non-alcoholic fatty liver disease | Diabetes | |
| GCSH | 16 | q23.2 | GLYCINE ENCEPHALOPATHY | Autism spectrum | |
| GDF1 | 19 | p13.11 | heterotaxy syndrome | Heterotaxy | |
| GDF3 | 12 | p13.31 | Microphthalmia isolated with coloboma 3 (MCOPCB3) | Microphthalmia | |
| GDF6 | 8 | q22.1 | Microphthalmia isolated with coloboma 3 (MCOPCB3) | Microphthalmia | |
| GDNF | 5 | p13.2 | GILLES DE LA TOURETTE SYNDROME | Autism spectrum | |
| GEFSP9 | 16 | p11.2 | GENERALIZED EPILEPSY WITH FEBRILE SEIZURES PLUS TYPE 9 | Autism spectrum | |
| GFAP | 4 | q21.31 | Alexander disease | Ataxia spectrum | |
| GGT1 | 11 | q11.23 | gamma-Glutamyltransferase deficiency | Polymorphous light eruption | |
| GGT8P | 2 | p11.1-2 | Autism 18 (AUTS18) | Autism spectrum | |
| GHR | 5 | p13.1 | Type 2 Diabetes | Diabetes | |
| GIF | 11 | q12.1 | Hereditary intrinsic factor deficiency | Vitamin B12 metabolism spectrum | |
| GIGYF1 | 7 | q22.1 | Autism 18 (AUTS18) | Autism spectrum | |
| GIGYF2 | 2 | q37.1 | Parkinson Disease type 11 | Parkinsonism | |
| GJA1 | 6 | q22.31 | Oculodentodigital dysplasia | Microcephaly | |
| GJA1 | 6 | q22.31 | heterotaxy syndrome | Heterotaxy | |
| GJA3 | 13 | q12.11 | Zonular pulverulent cataract type 3 (CZP3) | Cataracts | |
| GJA5 | 1 | q21.1 | 1q21.1 bradycardia | Bradycardia (<60 beats/minute) | |
| GJA8 | 1 | q21.1 | Cataract 01 multiple types (CTRCT1) | Cataracts | |
| GJB2 | 13 | q12.11 | Keratitis-ichthyosis-deafness syndrome | Photophobia - sensitivity to light | |
| GJB6 | 13 | q12.11 | Clouston syndrome | Alopecia | |
| GJC2 | 1 | q42.13 | Pelizaeus-Merzbacher-like disease type 01 | Ataxia spectrum | |
| GLDC | 9 | p24.1 | GLYCINE ENCEPHALOPATHY | Autism spectrum | |
| GLE1 | 9 | q34.11 | Lethal arthrogryposis with anterior horn cell disease | Arthrogryposis spectrum | |
| GLI2 | 2 | q14.2 | Microcephaly - other | Microcephaly | |
| GLIS3 | 9 | p24.2 | Diabetes mellitus neonatal with congenital hypothyroidism | Diabetes | |
| GLIS3 | 9 | p24.2 | Congenital hypothyroidism | Hypothyroidism | |
| GLO1 | 6 | p21.2 | GLYOXALASE I | Autism spectrum | |
| GLOW | 14 | q32.13 | GLOBAL DEVELOPMENTAL DELAY LUNG CYSTS OVERGROWTH WILMS TUMOR | Autism spectrum | |
| GLRA1 | 5 | q33.1 | hereditary hyperekplexia | Epilepsy and seizures | |
| GLRB | 4 | q32.1 | hereditary hyperekplexia | Epilepsy and seizures | |
| GLUD1 | 10 | q23.2 | Congenital hyperinsulinism | Diabetes | |
| GLUD2 | 23 | q24 | Parkinson disease susceptability | Parkinsonism |
| GLYCTK | 3 | p21.2 | D-GLYCERIC ACIDURIA | Autism spectrum | |
| GNAI3 | 1 | p13 | Auriculo-condylar syndrome | Cleft lip / cleft palate | |
| GNAS | 20 | q13.32 | McCune-Albright syndrome (overactive thyroid) | Hyperthyroidism | |
| GNAS | 20 | q13.3 | McCune-Albright syndrome | Tachycardia (>100 beats/minute) | |
| GNAT2 | 1 | p13.3 | Achromatopsia | Photophobia - sensitivity to light | |
| GNPAT | 1 | q42.2 | Rhizomelic chondrodysplasia punctata type 2 | Rhizomelic chondrodysplasia punctata | |
| GPC1 | 2 | q35-37 | Alzheimer - late onset | Alzheimer Syndrome | |
| GPHN | 14 | q22.3 | Molybdenum cofactor deficiency | Microcephaly | |
| GPHN | 14 | q23.3 | hereditary hyperekplexia | Epilepsy and seizures | |
| GPI | 19 | q13.1 | Glucose phosphate isomerase deficiency | Tachycardia (>100 beats/minute) | |
| GPIBD11 | 17 | q12 | GLYCOSYLPHOSPHATIDYLINOSITOL BIOSYNTHESIS DEFECT 11 | Autism spectrum | |
| GPIBD17 | 14 | q24.1 | GLYCOSYLPHOSPHATIDYLINOSITOL BIOSYNTHESIS DEFECT 17 | Autism spectrum | |
| GPR143 | 23 | p22.2 | Ocular albinism type 1 | Photophobia - sensitivity to light | |
| GPX1 | 3 | p21.31 | Glutathione peroxidase deficiency | Pervasive Developmental Delay | |
| GRIA3 | 23 | q25 | Mental retardation X-linked 94 (MRX94) | Autism spectrum | |
| GRID2 | 4 | q22.1-2 | Spinocerebellar ataxia autosomal recessive type 18 | Ataxia spectrum | |
| GRIN1 | 9 | q34.3 | GLUTAMATE RECEPTOR IONOTROPIC N-METHYL-D-ASPARTATE SUBUNIT 1 | Autism spectrum | |
| GRIN2A | 16 | p13 | EPILEPSY FOCAL WITH SPEECH DISORDER | Autism spectrum | |
| GRIN2B | 12 | p13.1 | Mental retardation autosomal dominant 06 (MRD6) | Autism spectrum | |
| GRIP1 | 12 | q14.3 | Fraser syndrome | Cleft lip / cleft palate | |
| GRM5 | 11 | q14.2-q14. | GLUTAMATE RECEPTOR METABOTROPIC 5 | Autism spectrum | |
| GRPR | 23 | p22.2 | GASTRIN-RELEASING PEPTIDE RECEPTOR | Autism spectrum | |
| GSN | 9 | q33 | Lattice corneal dystrophy type II | Cerebral palsy | |
| GSR | 8 | p12 | gamma-Glutamyltransferase deficiency | Polymorphous light eruption | |
| GSTTP2 | 22 | q11.23 | Autism 18 (AUTS18) | Autism spectrum | |
| GTF2I | 7 | q11.23 | 7q11.23 duplication syndrome | Panic phobia anxiety | |
| GTF2IRD1 | 7 | q11.23 | Williams syndrome | Panic phobia anxiety | |
| GUCY2D | 17 | p13.1 | Leber congenital amaurosis | Photophobia - sensitivity to light | |