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skin in the inner corner of the eye, and drooping eyelids. The woman also may have diabetes mellitus, cataracts, rheumatoid arthritis, and cardiac abnormalities in addition to chronic thyroiditis.

Viewing the Future of Managing Hereditary Thyroid Disease Up to now, scientists haven’t been successful in their attempts to remove a “bad” gene from a human and replace it with a healthy gene — a process known as genetic engineering. The problem is that they don’t yet know how to insert the new gene successfully. If scientists can determine how to do so, they can open the door to preventing diseases that people inherit through a single gene.

Genetic engineering If a recessive gene causes a disease, replacing that gene with its dominant form in sufficient amounts should be enough to cure the condition. Usually in a recessive-gene disorder, the disease occurs because that particular gene isn’t functioning at all, so providing even a small level of function may cure the condition. The disorders that may most easily respond to genetic engineering are disorders of the blood system, because doctors and scientists may easily remove blood. A new gene can be spliced into the cells and the blood reintroduced to the patient. The first trial of gene therapy, performed in 1990, was for a disorder that resulted in severe loss of immunity so that the patient was very susceptible to any infection, as well as a cancer. Scientists were able to introduce the necessary gene into the blood cells of the patient by connecting the gene to a virus, which infected the cells and added the gene to their DNA. The cells were grown to increase their number and reinserted. Unfortunately, the trial didn’t work, probably because the efficiency of splicing the gene into the cells was low. Other genetic disorders for which trials of gene therapy have taken place include Familial hypercholesterolemia: Excessive production of cholesterol leads to early death by heart attack. Cystic fibrosis: Lack of a certain gene leads to excessive production of a thick mucous in the lungs, resulting in chronic lung infection.

Thyroid for dummies  
Thyroid for dummies  
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