Genetic Disease hormone

Tyrosine is a precursor of thyroid hormones as well as L-dopa. Both thyroxine and L-dopa are employed in clinical medicine thyroxine to treat hypothyroid patients and L-dopa to treat patients with Parkinsonism. L-dopa is also the precursor to the pigment of the skin known as melanin. The enzyme that catalyzes the transformation of tyrosine into L-dopa, tyrosine hydroxylase, also catalyzes the transformation of L-dopa into melanin. Albinism is a genetic disease in which a mutation in the gene encoding tyrosine hydroxylase results in an inactive enzyme. People with albinism have no pigment in their skin, hair, or retina. 

There are many factors, both chemical and biological, which affect the disposition of xenobiotics. Chemical factors include size and structure, pKa, chirality, and lipophilicity. Biological factors include species, sex and strain, genetic factors, hormonal influences, disease and pathological conditions, age, stress, diet, dose, enzyme induction and inhibition, and tissue and organ specificity. All of these factors can affect the toxicity of a chemical by changing its disposition, especially its metabolism. 

Genetic disease Vitamin D metabolism is adversely affected in a rare genetic disease that results in impairment of the conversion of vitamin Dj to the hormonally active form. The disease affects l-hydroJ(ylase an enzyme of the kidney. 

The development of analog-specific forms of nudear/steroid hormone receptors has prompted us to investigate many naturally occurring mutations found in nuclear receptors assodated with genetic disease. Mutations to... 

Body fluid osmolality is controlled by a homeostatic mechanism that adjusts both the rate of water intake and the rate of solute-free water excretion by the kidneys—i.e., water balance. Abnormah-ties in this homeostatic system can result from genetic diseases, acquired diseases, or drugs, and may cause serious and potentially life-threatening deviations in plasma osmolality. Arginine vasopressin is the main hormone that regulates body fluid osmolality. 

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