Antley-Bixler Syndrome (ABS)

Cytochrome P450 oxidoreductase (POR) deficiency is a disorder of steroidogenesis associated with a broad range of clinical presentations. Steroid abnormalities occur in all patients, consistent with a form of congenital adrenal hyperplasia (CAH) causing deficiencies of both 21-hydroxylase and 17?-hydroxylase/17,20-lyase; therefore, some patients with POR deficiency may have an abnormal newborn screen for 21-hydroxylase deficiency. Like classical CAH, the steroid abnormalities may lead to cortisol deficiency, which in some cases can be life-threatening without treatment (Fukami et al., 2005). Disordered sex development can be observed in both males and females, and ambiguous genitalia is a common finding. At the severe end of the spectrum, patients may also have skeletal and craniofacial findings consistent with Antley-Bixler syndrome, including craniosynostosis, brachycephaly, severe midface hypoplasia, radiohumeral synostosis, and multiple joint contractures

Tests Available

Forms and Documents

Test Details

POR
  • 1. Confirmation of a clinical and/or biochemical diagnosis
  • 2. Carrier testing in at-risk family members
  • 3. Prenatal diagnosis for known mutations
  • Capillary Sequencing

Ordering

339
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)|Buccal Swabs

Billing

81479x1
No
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Fluck et al. (2004) Curr Opin Pediatr 18:435-441
  2. Reardon et al. (2000) J Med Genet 37:26-32
  3. Scott et al. (2008) Horm Res 69:266-275
  4. Huang et al. (2005) Am J Hum Genet 76:729-749
  5. Fukami et al. (2005) J of Clin Endocrinol Metab 90(1):414-426

Forms and Documents

Test Details

POR
  • Full gene sequencing for fetuses with prenatal ultrasound findings suggestive of Antley-Bixler syndrome or cytochrome P450 Oxidoreductase (POR) deficiency
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Capillary Sequencing

Ordering

907
2-3 weeks
20 mL Amniotic Fluid
20 mg CVS|2 T25 flasks of cultured amniocytes|2 T25 flasks of cultured chorionic villi|3 Ug DNA Concentration

Billing

81479x1, 81265x1
No
No
* For price inquiries please email zebras@genedx.com