IQSEC1 and Delayed speech and language development: Using TGex software (LifeMap Sciences, United States), 9 candidate variants in 9 genes (UBAP2L, CUX2, CACNA1I, SAMD12, HERC2, IQSEC1, NFASC, RERE, PLAA) were mapped to known phenotypes including seizures, intellectual disability, developmental delay, motor delay, language delay and autistic behaviour.