TABLE 3.
Genotype–phenotype data from the literature
| Variants | Neonatal feeding difficulties | Intellectual disability | Autistic features | Hypotonia | Tonic–clonic seizures | Absence seizures | Refractory seizures | Brain abnormalities | Cardiac abnormalities | Variant identified by |
|---|---|---|---|---|---|---|---|---|---|---|
| Splice site variants | ||||||||||
| c.692‐1G>A p.? | − | + | − | − | − | − | − | − | − | Depienne et al. (2017) |
| c.2425‐3C>A p.? | − | + | + | − | + | + | − | + | − | Depienne et al. (2017) |
| c.1117+1G>A p.? | − | + | − | + | − | − | − | − | − | Yates et al. (2017) |
| c.1743+1G>C p.? | + | + | − | − | + | + | − | − | − | Durkin et al. (2020) |
| c.692‐1G>A p.? | − | − | − | − | − | − | − | − | + | Durkin et al. (2020) |
| c.2425‐2A>G p.? | + | + | − | + | − | − | − | + | + | This study |
| c.143‐149del7 p.? | − | − | − | − | + | − | − | − | + | Song et al. (2021) |
| c.878‐9T>G p.? | + | + | + | − | + | + | − | + | + | This study |
| c.804‐9_804‐6del p.? | + | + | + | + | − | − | − | − | − | This study |
| Nonsense variants | ||||||||||
| c.508C>T p.(Gln170*) | − | + | + | − | − | − | − | − | − | This study |
| c.619C>T p.(Gln207*) | + | − | − | − | − | + | − | − | − | Durkin et al. (2020) |
| c.1450C>T p.(Arg484*) | − | − | − | − | − | − | − | − | − | Durkin et al. (2020) |
| c.67C>T p.(Arg23*) | + | − | − | − | − | − | − | − | − | Durkin et al. (2020) |
| c.1088G>A p.(Trp363*) | − | + | − | − | − | − | − | − | + | Durkin et al. (2020) |
| c.1801C>T p.(Arg601*) | − | + | + | − | − | − | − | − | − | Durkin et al. (2020) |
| c.1089G>A p.(Trp363*) | − | + | + | + | + | + | + | + | + | Durkin et al. (2020) |
| c.960G>A p.(Trp320*) | − | + | − | + | + | − | − | − | − | Yates et al. (2017) |
| c.1714C>T p.(Arg572*) | − | + | − | + | + | − | − | + | − | Leduc et al. (2017) |
| c.1089G>A p.(Trp363*) | − | + | + | + | + | + | + | + | + | Leduc et al. (2017) |
| c.817C>T p.(Gln273*) | + | + | − | + | − | − | − | − | + | Bramswig et al. (2017) |
| c.511C>T p.(Gln171*) | + | + | − | + | + | − | − | + | + | Bramswig et al. (2017) |
| c.523C>T p.(Gln175*) | − | + | − | − | + | + | − | − | − | Bramswig et al. (2017) |
| c.1681C>T p.(Gln561*) | − | + | − | + | − | + | − | − | − | Depienne et al. (2017) |
| Missense variants | ||||||||||
| c.893A>G p.(His298Arg) | + | + | + | + | + | + | + | + | − | This study |
| c.418G>A p.(Glu140Lys) | + | + | + | − | − | − | − | − | + | Yates et al. (2017) |
| c.970A>G p.(Arg324Gly) | + | + | − | + | − | − | + | + | + | Bramswig et al. (2017) |
| c.1132T>C p.(Ser378Pro) | − | + | − | + | + | + | + | + | − | Bramswig et al. (2017) |
| c.1834G>A p.(Asp612Asn) | + | + | + | + | + | − | + | − | − | This study |
| In‐frame deletions | ||||||||||
| c.837_839del p.(Glu279del) | + | + | − | − | − | − | − | − | − | Durkin et al. (2020) |
| c.1744_1767del p.(Thr582_Gln589del) | − | + | + | + | + | − | − | − | − | Bramswig et al. (2017) |
| Frameshift duplications | ||||||||||
| c.1617dup p.(Ala540Glyfs*4) | − | + | − | − | − | − | − | − | − | This study |
| c.1868dup p.(Glu624Argfs*24) | − | + | − | + | + | − | − | − | − | Depienne et al. (2017) |
| c.742dup p.(Arg248Lysfs*12) | − | + | − | + | − | − | + | − | − | This study |
| Frameshift deletions | ||||||||||
| c.1836del p.(Tyr613Ilefs*11) | − | + | − | − | + | + | − | − | + | Durkin et al. (2020) |
| c.1641del p.(Asp548Ilefs*5) | − | + | − | − | + | + | − | − | − | Durkin et al. (2020) |
| c.1681del p.(Gln561Serfs*45) | − | + | + | + | + | + | + | + | + | Durkin et al. (2020) |
| c.23del p.(Val8Glufs*4) | − | + | − | − | − | − | − | − | − | Yates et al. (2017) |
| c.1664del p.(Leu555Argfs*51) | − | + | − | − | − | − | − | − | + | Yates et al. (2017) |
| c.1681del p.(Gln561Serfs*45) | + | + | + | + | + | + | + | + | + | Depienne et al. (2017) |
| c.1282delC p.(Gly429Alafs*53) | − | + | + | − | + | − | + | − | + | Song et al. (2021) |
| c.16delinsATT p.(Val6Ilefs*4) | − | + | − | + | + | − | − | + | − | Depienne et al. (2017) |
| c.1243del p.(Asp415Metfs*3) | − | + | − | + | + | + | − | + | + | This study |
| c.2304_2305del p.(Gly769Glufs*83) | − | + | − | − | − | − | − | + | − | This study |
| c.730_731delAG p.(Arg244Glyfs*3) | + | + | − | + | − | − | − | − | − | This study |
| c.1665_1666delGT p.(Leu556Alafs*12) | + | + | − | − | − | − | − | − | − | This study |
| c.2270_2271delCT p.(Pro757Argfs*7) | + | + | + | + | + | + | + | − | − | Leduc et al. (2017) |
| c.1925_1926del p.(Leu642Profs*5) | + | + | − | − | − | − | − | − | + | Durkin et al. (2020) |
| c.395_401del p.(Asn132Thrfs*63) | + | − | − | − | + | − | − | − | − | Durkin et al. (2020) |
| c.2083_2084del p.(Ser695Trpfs*6) | − | − | − | − | + | − | − | − | − | Durkin et al. (2020) |
| c.706_707del p.(Glu236Thrfs*6) | + | + | + | + | + | + | + | + | + | Durkin et al. (2020) |
| c.454_466del p.(Ala152Thrfs*41) | − | + | + | − | − | + | − | − | − | Durkin et al. (2020) |
| c.706_707del p.(Glu236Thrfs*6) | − | + | + | + | + | + | + | + | + | Durkin et al. (2020) |
| c.712_715del p.(Lys238Alafs*100) | − | − | + | − | − | − | − | − | − | Durkin et al. (2020) |
| c.1626_1627insA p.(Lys544Glufs*25) | − | + | − | − | − | + | − | − | − | Yates et al. (2017) |
| c.1424_1425insTC p.(Ile476Profs*7) | − | + | + | − | − | + | + | − | − | Yates et al. (2017) |
| c.651_660del p.(Gly218Alafs*118) | − | + | − | + | + | − | − | + | − | Leduc et al. (2017) |
| c.2270_2271del p.(Pro757Argfs*7) | − | + | − | + | − | + | − | − | − | This study |
| c.2299_2302del p.(Asn767Glufs*66) | − | + | − | + | − | − | − | + | − | Depienne et al. (2017) |
| c.847_857del p.(Phe283Serfs*5) | − | + | + | + | + | + | + | + | + | Durkin et al. (2020) |
| Multi‐exon deletion | ||||||||||
| c.2167+35_*4156del p.? | − | + | − | − | − | − | − | − | + | Durkin et al. (2020) |
Note: Variant nomenclature in each table is according to gene transcript NM_031844.2.