Table 2.

Characteristics of epilepsy-associated variants that were found in the EVS database.

Gene	SCN1A	SCN1A	SCN1A	SCN1B	EFHC1	EFHC1	EFHC1
Mutation	T297I	E1957G	R1596C	C121W	F229L	P77T	R221H
De Novo?	familial	unknown	De novo	familial	familial	familial	familial
Segregates with disease in family?	no			no	no	no	no
Frequency In EVS	1/13001	5/13001	1/13005	1/13005	43/12963	107/12899	105/12901
European American	1/8595	5/8595	1/8599	1/8599	41/8559	0/8600	0/8600
African American	0/4406	0/4406	0/4406	0/4406	2/4404	107/4299	105/4301
phastCons	0.068	1	1	1	1	0.103	0.905
GERP	5.41	5.67	5.9	3.17	6.01	3.13	2.2
Grantham Score	89	98	180	215	22	38	29
PolyPhen	probably-damaging	benign	probably-damaging	probably-damaging	possibly-damaging	benign	benign

The PhastCons score reflects the probability that a base is conserved between 17 vertebrate species. The Genomic Evolutionary Rate Profiling Score (GERP) is another measure of conservation ranging from −12.3 to 6.17, with 6.17 being the most conserved. The Grantham score ranks codon replacement by increasing chemical dissimilarity. The PolyPhen prediction uses the Polymorphism Phenotyping program to predict the possible impact of an amino acid substitution on a protein.