stop codon 14 Humans 10 genetics 10 human 10 Article 6 Codon, Terminator 6 article 6 exon 6 genetic variability 6 heterozygosity 6 nonhuman 6 Female 4 Male 4 Mutation 4 Sanger sequencing 4 Substrate Specificity 4 amino acid substitution 4 bioinformatics 4 codon 4 controlled study 4 disease severity 4 epilepsy 4 family history 4 female 4 gene deletion 4 gene insertion 4 intellectual impairment 4 male 4 metabolism 4 missense mutation 4