title: IL1RAPL1 gene deletion as a cause of X-linked intellectual disability and dysmorphic features.
abstract: Intellectual disability affects approximately 2% of the population with males outnumbering females due to involvement of over 300 genes on the X chromosome. The most common form of X-linked intellectual disability (XLID) is fragile X syndrome. We report a family with an apparent XLID pattern with the proband, his mother and maternal half brother having an Xp21.3 deletion detected with chromosomal microarray analysis involving the interleukin 1 receptor accessory protein-like 1 (IL1RAPL1) gene. IL1RAPL1 is highly expressed in the postnatal brain, specifically hippocampus suggesting a specialized role in memory and learning abilities. The proband presented with intellectual disability, a broad face, prominent and wide nasal root, ptosis, a wide philtrum and a small mouth. XLID due to involvement of the IL1RAPL1 gene has been reported to cause nonsyndromic XLID. We report a new family with XLID due to partial deletion of IL1RAPL1, summarize reported literature and describe similar phenotypic similarities among the affected individuals in this family and those reported in the literature proposing that deletion of IL1RAPL1 may cause syndromic XLID. Additional reports are needed to further characterize whether syndromic features are related to disturbances of this gene.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Kansas Medical Center, Kansas City, KS, United States. eyoungs@saint-lukes.org
authors.forename: Erin L
authors.initials: EL
authors.lastname: Youngs
authors.forename: Rebecca
authors.initials: R
authors.lastname: Henkhaus
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Hellings
authors.forename: Merlin G
authors.initials: MG
authors.lastname: Butler
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics / Q000473:pathology; D000293:Adolescent; D041321:Chromosomes, Human, X / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D005820:Genetic Testing; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology; D006801:Humans; D053577:Interleukin-1 Receptor Accessory Protein / Q000235:genetics*; D008297:Male; D038901:X-Linked Intellectual Disability / Q000235:genetics* / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010375:Pedigree; D010641:Phenotype
chemical_list: C407643:IL1RAPL1 protein, human; D053577:Interleukin-1 Receptor Accessory Protein