All individuals have or had global developmental delay in childhood, and as older children or young adults, all have language delay and the majority (93%) have some degree of intellectual disability. A smaller percentage have formal autism or attention-deficit/hyperactivity disorder (ADHD) diagnoses (36% and 29% respectively), but again, almost all cases have autistic features and behavioral difficulties as a component of the phenotype. These often include easy excitability, hypersensitivity to sensory stimuli, high pain threshold, anxiety, emotional dysregulation and aggression. Less than half had sleep challenges noted.
Dysmorphisms were subtle and nonspecific if present (abnormalities of the hands and feet were most common at 50%). Both macrocephaly and microcephaly were observed. MRI findings were not uniformly available, but just under half of those that were performed reported a finding (Dandy-Walker malformation or cerebellar tonsillar herniation, abnormality of basal ganglia, delayed myelination, cortical dysplasia ). Seizures were reported in 2 of the 14 individuals (one with absence and generalized and the other with myoclonic). Thus far, there are only slightly more males identified compared to females but no sex-based differences in phenotype severity.
RFX7