Table 1.

Probably pathogenic variants confirmed in follow‐up

ID	Sex	Genotype	Gene	Variant (aa)a	Expected gene inheritance	Family tested	OMIM morbid descriptionb
2012D09029	M	Hemi	CASK	p.R584X	X‐linked	De novo	Mental retardation and microcephaly with pontine and cerebellar hypoplasia
2008D06721	F	Hetero	EEF1A2	p.G70S	Dominant	De novo	Epileptic encephalopathy, early infantile, 33
EG1761	F	Hetero	FARS2	p.T156M	Recessive	Compound het	Combined oxidative phosphorylation deficiency 14
EG1761	F	Hetero	FARS2	c.905‐1G>A (splice‐acceptor)	Recessive	Compound het	Combined oxidative phosphorylation deficiency 14
EP2201	F	Hetero	GNAO1	p.G40R	Dominant	De novo	Epileptic encephalopathy, early infantile, 17
EP2822	M	Hetero	GPHN	p.D422N	Recessive	Compound het	Molybdenum cofactor deficiency, complementation group c
EP2822	M	Hetero	GPHN	c.1315‐2A>G (splice‐acceptor)	Recessive	Compound het	Molybdenum cofactor deficiency, complementation group c
EP1718	M	Homo	GRIN1	p.Q556X	Dominant	Inherited from het parents	Mental retardation, autosomal dominant 8
EP2797	M	Hetero	GRIN1	p.G827R	Dominant	De novo	Mental retardation, autosomal dominant 8
2012D06376		Hetero	HNRNPU	pV604 fs	Dominant	De novo	Candidate
2010D12136	M	Hemi	IQSEC2	p.Y1129X	X‐linked	De novo	Mental retardation, x‐linked 1
EP1961	F	Hetero	IQSEC2	p.G771D	X‐linked	De novo	Mental retardation, x‐linked 1
2010D05815	F	Hetero	KCNB1	p.F416L	Dominant	De novo	Epileptic encephalopathy, early infantile, 26
KIEL20	M	Hetero	KCNB1	p.R312H	Dominant	De novo	Epileptic encephalopathy, early infantile, 26
2012D20026	M	Hetero	KCNQ2	p.Y363H	Dominant	De novo	Epileptic encephalopathy, early infantile, 7
KIEL42	F	Hetero	KCNQ2	p.R532W	Dominant	De novo	Epileptic encephalopathy, early infantile, 7
2009D12616	F	Hetero	KCNT1	p.R429C	Dominant	Not tested	Epileptic encephalopathy, early infantile, 14
EP2788	F	Hetero	KCNT1	p.R429H	Dominant	De novo	Epileptic encephalopathy, early infantile, 14
EP95	M	Hetero	KCNT1	p.R429C	Dominant	De novo	Epileptic encephalopathy, early infantile, 14
1011L	F	Homo	PNKP	p.A420 fs	Recessive	Inherited from het parents	Epileptic encephalopathy, early infantile, 10
395M	F	Homo	POLG	p.R1096C	Recessive	Inherited from het parents	Leigh syndrome
EP1781	F	Hetero	SCN1A	p.C968G	Dominant	De novo	Epileptic encephalopathy, early infantile, 6
EUR577	F	Hetero	SCN1A	p.I1347T	Dominant	De novo	Epileptic encephalopathy, early infantile, 6
KIEL38	M	Hetero	SCN1A	p.D702 fs	Dominant	De novo	Epileptic encephalopathy, early infantile, 6
EP1789	F	Hetero	SCN2A	p.L1665F	Dominant	De novo	Epileptic encephalopathy, early infantile, 11
EP2104	M	Hetero	SCN2A	p.Q1811E	Dominant	De novo	Epileptic encephalopathy, early infantile, 11
2010D14438	F	Hetero	SLC13A5	p.S427L	Recessive	Compound het	Epileptic encephalopathy, early infantile, 25
2010D14438	F	Hetero	SLC13A5	p.G219R	Recessive	Compound het	Epileptic encephalopathy, early infantile, 25
EP2821	F	Homo	SLC25A22	p.Q117R	Recessive	Inherited from het parents	Epileptic encephalopathy, early infantile, 3
EP2806	F	Hetero	SPTAN1	p.R2037W	Dominant	De novo	Epileptic encephalopathy, early infantile, 5
EP2514	M	Hetero	STXBP1	p.P480L	Dominant	De novo	Epileptic encephalopathy, early infantile, 4
2013D03222	M	Double het	TBC1D24	p.E153K	Recessive	Testing	Epileptic encephalopathy, early infantile, 16
2013D03222	M	Double het	TBC1D24	p.H336 fs	Recessive	Testing	Epileptic encephalopathy, early infantile, 16
2008D07479	F	Hetero	WDR45	p.E155X	X‐linked dominant	De novo	Neurodegeneration with brain iron accumulation 5; SENDA

Compound heterozygotes are shaded in gray.

^aComplete notation with accession numbers can be found in the supplementary table.

^bMorbid description in OMIM. Only the most relevant phenotype is listed here.