Cantagrel et al. describe a family with two affected males with severe intellectual disability. Both males (an uncle and a nephew) presented with neonatal hypotonia, severe developmental delays, progressive quadriparesia, gastroesophageal reflux, autism, steryotypical hand movements, and mildly dysmorphic features. One of the affected individuals had tonic-clonic seizures as well.
A pericentric inversion (inv(X)(p22;q13)) was identified in both males and their unaffected obligate carrier mothers. One of the genes disrupted by the inversion is the KIAA2022 gene (Xq13.3) which is highly expressed in fetal brain and adult cerebral cortex. The KIAA2022 transcript was no longer expressed in the affected males; however, it was indistinguishable from the wildtype in the cells from the carrier mothers.
- OMIM #300524: KIAA2022 gene
- Cantagrel et al. (2004). J Med Genet, 41:736-742
- Confirmation of a clinical diagnosis of KIAA2022-Related X-linked Mental Retardation in an individual in whom sequence analysis was negative.
- Carrier testing in adults with a family history of KIAA2022-Related X-linked Mental Retardation in an individual in whom sequence analysis was negative.
Please note that a "backbone" of probes across the entire genome are included on the array for analytical and quality control purposes. Rarely, off-target copy number variants causative of disease may be identified that may or may not be related to the patient's phenotype. Only known pathogenic off-target copy number variants will be reported. Off-target copy number variants of unknown clinical significance will not be reported.
Submit only 1 of the following specimen types
Preferred specimen type: Whole Blood
Type: Whole Blood
Specimen Requirements:In EDTA (purple top) or ACD (yellow top) tube:
Infants (<2 years): 2-3 ml
Children (>2 years): 3-5 ml
Older Children & Adults: 5-10 ml
Specimen Collection and Shipping: Refrigerate until time of shipment. Ship sample within 5 days of collection at room temperature with overnight delivery.
Specimen Requirements:OrageneTM Saliva Collection kit (available through EGL) used according to manufacturer instructions.
Specimen Collection and Shipping: Store sample at room temperature. Ship sample within 5 days of collection at room temperature with overnight delivery.
- Sequence analysis of the KIAA2022 gene is available and is required before deletion/duplication analysis.
- Custom diagnostic mutation analysis (KM) is available to family members if mutations are identified by targeted mutation testing or sequencing analysis.
- Prenatal testing is available only for known familial mutations to individuals who are confirmed carriers of mutations. Please contact the laboratory genetic counselor to discuss appropriate testing prior to collecting a prenatal specimen.
- X-Linked Intellectual Disability panels are available for 30, 60, and 90+ genes.