In females, more than 85% of the cases are due to nonsense mutations of the CASK gene, whereas 38~63% of the cases are caused by nonsense mutations in males (p < 0.0001, intellectual disability; p < 0.0001, MICPCH; p < 0.0001, epilepsy; p = 0.0169, opthalmological anomalies; statistically significant in all cases, see Figure 2). Here, CASK is linked to Intellectual disability.