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Ethnic Link to Thyroid Disease

Ethnicity affects rates of the thyroid disorder Graves’ disease, according to a study of medical data from American military personnel.

The thyroid gland is found in the front of the neck, below the larynx, and helps to regulate metabolism. Graves’ disease is a condition that causes an overactive thyroid, speeding up metabolism. It affects about 1% of the population.

Dr Don McLeod of the QIMR Berghofer Medical Research Institute found that Graves’ disease was almost twice as common in African Americans and Asian/Pacific Islanders than in Caucasian women and more than two-and-a-half times more common than in Caucasian men.

“We don’t yet know whether the differences seen are due to genetics, environmental exposures or a combination of both,” McLeod said. “But if these differences are due to racial variations in immune system pathways, in the future we could use this information to design new treatments or prevention for autoimmune disease.

“If environmental exposures were the cause, we could educate and empower people to avoid these exposures and prevent disease.

“Graves’ disease has a significant impact on sufferers, and without treatment can be life-threatening. It also causes eye disease and pregnancy complications including miscarriage and problems with foetal development,” McLeod said.

The next step for researchers is to confirm that the racial links observed are seen in the wider population and aren’t specific to the US military.

“Finding the root causes of thyroid autoimmunity has the potential to lead to prevention of thyroid disorders, and may also lead to crucial insights into other autoimmune disease,” McLeod said.

The study was published in JAMA.