| Phenotype details |
16m-eye-tracking; no speech, no two-word sentences; 16m-stable head and neck, 2y-rolling over, 3y-crawled; never sitting alone, never walked; intellectual disability; autistic features; 4m onset early infantile epileptic encephalopathy; no dysmorphology; no cardiac features; hypotonia; no involuntary movement; no skeletal anomalies; visual perceptual disorder; elevated lactate; MRI brain abnormal |