Syndromic X-Linked Mental Retardation, Turner Type
Missence mutations in the HUWE1 gene were identified in several families with a syndromic form of XLID. The clinical presentation is variable with the ID ranging from moderate to profound. Additional features that can be present include macrocephaly and speech/language delay or absent speech. No dysmorphic features were reported.
X-Linkied Mental Retardation 17
Microduplications of chromosome Xp11.22, including both the HSD17B10 and the HUWE1 genes, cause a nonsyndromic form of X-linked intellectual disability (XLMR 17). The intellectual disability is mild to moderate in severity.
For patients with suspected HUWE1-related XLID, sequence analysis is recommended as the first step in mutation identification. For patients in whom mutations are not identified by full gene sequencing, deletion/duplication analysis is appropriate.
- Confirmation of a clinical diagnosis of HUWE1-related XLID.
- Carrier testing in adults with a family history of HUWE1-related XLID.
Analytical Sensitivity: ~99%
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.
- Deletion/duplication analysis of the HUWE1 gene by CGH array is available for those individuals in whom sequence analysis is negative.
- 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.