IL1RAPL1 and Cognitive impairment: Deletions and point mutations in IL1RAPL1 are the cause of nonsyndromic MR X-linked type 2.[21] Studies have shown that the inactivation of the IL1RAPL1 gene can lead to cognitive deficits in both male and female mutation carriers.[21,22,26] The IL1RAP duplication therefore could have contributed to the phenotypic abnormalities in our case.