Point mutation of Arg440 to his in cytochrome P450c17 causes severe 17{alpha}-hydroxylase deficiency
- Univ. of California, San Francisco, CA (United States)
- Univ. of Ulm (Germany)
Genetic disorders in the gene encoding P450c17 cause 17{alpha}-hydroxylase deficiency. The consequent defects in the synthesis of cortisol and sex steroids cause sexual infantilism and a female phenotype in both genetic sexes as well as mineralorcorticoid excess and hypertension. A 15-yr-old patient from Germany was seen for absent pubertal development and mild hypertension with hypokalemia, high concentrations of 17-deoxysteroids, and hypergonadotropic hypogonadism. Analysis of her P450c17 gene by polymerase chain reaction amplification and direct sequencing showed mutation of codon 440 from CGC (Arg) to CAC (His). Expression of a vector encoding this mutated form of P450c17 in transfected nonsteroidogenic COS-1 cells showed that the mutant P450c17 protein was produced, but it lacked both 17{alpha}-hydroxylase and 17,20-lyase activities. To date, 15 different P450c17 mutations have been described in 23 patients with 17{alpha}-hydroxylase deficiency, indicating that mutations in this gene are due to random events. 36 refs., 3 figs., 2 tabs.
- OSTI ID:
- 54490
- Journal Information:
- Journal of Clinical Endocrinology and Metabolism, Journal Name: Journal of Clinical Endocrinology and Metabolism Journal Issue: 1 Vol. 79; ISSN JCEMAZ; ISSN 0021-972X
- Country of Publication:
- United States
- Language:
- English
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