Isovaleric acidemia is a rare autosomal recessive, metabolic disorder which disrupts or prevents normal metabolism of the branched-chain amino acid leucine. It is a classical type of organic acidemia. A characteristic feature of isovaleric acidemia is a distinctive odor of sweaty feet. This odor is caused by the buildup of a compound called isovaleric acid in affected individuals. In about half of cases, the signs and symptoms of this disorder become apparent within a few days after birth and include poor feeding, vomiting, seizures, and lack of energy that can progress to coma. These medical problems are typically severe and can be life-threatening. In the other half of cases, the signs and symptoms of the disorder appear during childhood and may come and go over time. They are often triggered by an infection or by eating an increased amount of protein-rich foods.
Mutations in both copies of the IVD gene result in isovaleric acidemia. The enzyme encoded by IVD, isovaleric acid-CoA dehydrogenase, plays an essential role in breaking down proteins from the diet. Specifically, the enzyme is responsible for the third step in processing leucine, an essential amino acid. If a mutation in the IVD gene reduces or eliminates the activity of this enzyme, the body is unable to break down leucine properly. As a result, isovaleric acid and related compounds build up to toxic levels, damaging the brain and nervous system. Treatment consists of dietary protein restriction, particularly leucine. During acute episodes, glycine is sometimes given, which conjugates with isovalerate forming isovalerylglycine, or carnitine which has a similar effect.
Methodology: Sequencing of entire coding region of the IVD gene
Deletion/Duplication analysis is also available for this gene.
Purpose: Confirmation of Clinical Diagnosis
Detection Frequency: ~99%
Turn-Around-Time: 5 weeks (Please note on test order form if case is urgent and results are needed STAT)
Specimen Requirements: 2-5 ml Blood- EDTA tube (Lavender Top)
For Buccal Swab or Saliva samples please contact the lab to obtain a collection kit.
OUHSC Genetics Laboratory 1122 NE 13th Street, Suite 1400, Oklahoma City, OK 73104
Phone (405)271-3589 Fax (405)271-7117 After hours phone (405)496-9514
||Copyright © 2002
The Board of Regents of the University of Oklahoma, All Rights Reserved. OUHSC Home
Disclaimer | Copyright