Description:
ORNITHINE TRANSCARBAMYLASE DEFICIENCY, HYPERAMMONEMIA DUE TO; OTC
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Repository
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NIGMS Human Genetic Cell Repository
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| Subcollection |
Heritable Diseases
Disorders of the Urea Cycle |
| Quantity |
25 µg |
| Quantitation Method |
Please see our FAQ |
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Biopsy Source
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Peripheral vein
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Cell Type
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B-Lymphocyte
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Tissue Type
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Blood
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Transformant
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Epstein-Barr Virus
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Sample Source
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DNA from LCL
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Race
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Asian, Other
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Ethnicity
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Not Hispanic/Latino
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Family History
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Y
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Relation to Proband
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proband
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Species
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Homo sapiens
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Common Name
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Human
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Remarks
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| IDENTIFICATION OF SPECIES OF ORIGIN |
Species of Origin Confirmed by LINE assay |
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| Gene |
OTC |
| Chromosomal Location |
Xp21.1 |
| Allelic Variant 2 |
300461.0029; OTC DEFICIENCY |
| Identified Mutation |
ARG40HIS; Mavinakere et al. (2001) used (35)S labeling to study import and processing of OTC carrying the R40H mutation in intact CHO cells and in isolated rat liver mitochondria compared to wildtype and OTC carrying an R141Q mutant that causes complete enzyme deficiency. OTC protein carrying the R40H mutation seemed to be imported and processed by the mitochondria in a manner similar to that of wildtype. However, it was consistently degraded to a smaller fragment in the intact cells, unlike the wildtype and R141Q mutant. The mature form of the enzyme was not susceptible to degradation. Mavinakere et al. (2001) concluded that deficiency in OTC enzymatic function conferred by the R40H mutation is likely caused by enhanced degradation of the preprotein in the cytosol. The authors further proposed that the variation in the rate of OTC turnover is responsible for the heterogeneity of the clinical phenotype in patients carrying this mutation. |
| Remarks |
Clinically affected; onset of symptoms at age 18; pathogenic mutation in the OTC gene: 40G>A (Arg40His) |
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