Duplicationsof and in the SOX3 gene (Xq26.3) havebeen associated with X-linked recessive mental retardation with growth hormonedeficiency. Mental retardation is mild to moderate and growth hormone levelscan vary between affected individuals even within families. Some affected maleshave died during the first day of life and exhibited postmortem findings ofhypoadrenalism, presumably due to hypopituitarism. Others have variablecombinations of hypothyroidism, delayed pubertal development, and short staturedue to growth hormone deficiency. All surviving affected individuals exhibitedmild to moderate mental retardation. Behavior in affected individuals has beenconsidered infantile.
Variablecraniofacial dysmorphism has also been reported, including hypertelorism,epicanthus, synophrys, broad nasal bridge, high-arched palate, long philtrum, cuphelices, and coarse facies. In one study, male patients continued to grow untilwell into their twenties and reached a height ranging from 135 to 159 cm. BrainMRI in some affected males showed anterior pituitary hypoplasia, ectopicposterior pituitary, and absent infundibulum.
Click here for the OMIM summary on this condition.
This test is indicated for:
- Confirmation of a clinical/biochemical diagnosis of XLMR with growth hormone deficiency in individuals who have tested negative for sequence analysis
- Carrier testing in adult females with a family history of XLMR with growth hormone deficiency who have tested negative for sequence analysis
Infants and Young Children (<2 years of age): 2-3 ml
Children > 2 years of age to 10 years old: 3-5 ml
Older Children & Adults: 5-10 ml
Autopsy: 2-3 ml unclotted cord or cardiac blood
Isolation using the Perkin Elmer™Chemagen™ Chemagen™ Automated Extraction method or Qiagen™ Puregene kit for DNA extraction is recommended.
Submit copies of diagnostic biochemical test results with the sample, if appropriate. Contact the laboratory if further information is needed.
Sequence analysis is required before deletion/duplication analysis by targeted CGH array. If sequencing is performed outside of EGL Genetics, please submit a copy of the sequencing report with the test requisition.
- Sequencing analysis of the SOX3 gene is available (YV) and is required before deletion/duplication analysis.
- X-Linked Intellectual Disability panels are available for 30, 60, and 90+ genes.
- Prenatal testing is available to adult females who are confirmed carriers of mutations. Please contact the laboratory genetic counselor to discuss appropriate testing prior to collecting a prenatal specimen.