Ornithine Transcarbamylase (OTC) Deficiency

Ornithine Transcarbamylase (OTC) deficiency is the most common disorder of the urea cycle. Males usually present in the neonatal period with massively elevated ammonia levels and hyperammonemic coma, encephalopathy and respiratory alkalosis. However, the clinical features of OTC deficiency are highly variable ranging from an acute neonatal presentation with a high mortality rate to asymptomatic adult males. OTC is an Xlinked trait. Approximately 20% of females who are heterozygous for mutations in the OTC gene are clinically symptomatic with disease severity similar to males with partial deficiency. Both heterozygous females and partially deficient males may present with late onset of symptoms, even into adulthood, with recurrent vomiting, history of protein avoidance, Reye-like syndrome, or with major neurologic impairment, neurobehavioral changes or seizures associated with hyperammonemia.

Tests Available

Forms and Documents

Test Details

OTC
  • Confirmation of biochemical diagnosis
  • Identification of females heterozygous for a mutation
  • Prenatal diagnosis in at risk pregnancies
  • Capillary Sequencing
  • Exon Array CGH

Ordering

313E
4-5 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)|Buccal Swabs

Billing

81405x1, 81479x1
No
Yes
  • 270.6 Disorders of urea cycle metabolism, Argininosuccinic aciduria, Citrullinemia, Disorders of metabolism of ornithine, citrulline, argininosuccinic acid, arginine, and ammonia, Hyperammonemia, Hyperornithinemia
  • 277.8 Other specified disorders of metabolism
* For price inquiries please email zebras@genedx.com

References

  1. Yamaguchi, S., et al, (2006) Hum Mutat 27(7):626-632
  2. Tuchman, M., et al, (2002) Hum Mutat 19 :93-107
  3. Bowlig et al., (1999) Am J Med Genet 85:452
  4. Luksan et al., (2010) Hum Mutat 31:E1294-303
  5. Ogino et al., (2007) Kobe J Med Sci 53:229-240
  6. Tuchman, M., et al., (1998) Mol Genet Metab 21:40S- 58S

Forms and Documents

Test Details

OTC
  • Confirmation of biochemical diagnosis
  • Identification of males with partial enzyme deficiency
  • Prenatal diagnosis in at risk pregnancies
  • Capillary Sequencing

Ordering

313
4-5 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)|Buccal Swabs

Billing

81405x1
No
Yes
  • 270.6 Disorders of urea cycle metabolism, Argininosuccinic aciduria, Citrullinemia, Disorders of metabolism of ornithine, citrulline, argininosuccinic acid, arginine, and ammonia, Hyperammonemia, Hyperornithinemia
  • 277.8 Other specified disorders of metabolism
* For price inquiries please email zebras@genedx.com

References

  1. Ogino et al., (2007) Kobe J Med Sci 53:229-240
  2. Luksan et al., (2010) Hum Mutat 31:E1294-303
  3. Tuchman, M., et al., (1998) Mol Genet Metab 21:40S- 58S
  4. Bowlig et al., (1999) Am J Med Genet 85:452
  5. Yamaguchi, S., et al, (2006) Hum Mutat 27(7):626-632
  6. Tuchman, M., et al, (2002) Hum Mutat 19 :93-107