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HOMOCYSTINURIA: AN ENZYMATIC DEFECT.
Science (New York, N.Y.)
|March 27, 1964
Summary
A deficiency in cystathionine synthetase activity was found in the liver of a child with homocystinuria, a condition causing intellectual disability. This enzyme is crucial for metabolic processes.
Area of Science:
- Biochemistry
- Metabolic disorders
- Genetics
Background:
- Homocystinuria is a rare inherited metabolic disorder.
- Intellectual disability is a common symptom of untreated homocystinuria.
- Cystathionine synthetase is a key enzyme in the methionine metabolism pathway.
Purpose of the Study:
- To investigate the enzymatic basis of homocystinuria in a patient.
- To identify the specific enzyme deficiency responsible for the observed symptoms.
Main Methods:
- Liver biopsy was performed on the affected child.
- Enzyme activity assays were conducted on the liver tissue.
- Cystathionine synthetase activity was measured.
Main Results:
- A significant deficiency, or complete absence, of cystathionine synthetase activity was detected in the liver.
- This finding directly links the enzyme defect to the condition.
Conclusions:
- The study confirms a deficiency in cystathionine synthetase as the cause of homocystinuria in this patient.
- This enzymatic defect underlies the metabolic derangement leading to intellectual disability.
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