Evaluation of Mitochondrial Copy Number in Thyroid Disorders

The purpose of this study was to determine whether the mitochondrial DNA (mitDNA) copy number in blood samples of patients with thyroiditis, benign nodules or malignant nodules is different from that in healthy individuals, and to examine whether mtDNAcn has the ability to distinguish between different thyroid diseases.

This study consists of principal groups as thyroid patients and control group. The thyroid patient group comprised 30 patients with malignant nodules, 33 with benign nodules and 31 with thyroiditis, whereas the control group was composed of 21 healthy individuals. Blood samples were collected from the patients before treatment. Results were evaluated between groups.

We could not find an adequate number of participants for inclusion to match the groups. Similarly, since there is a gender difference in terms of disease prevalence, it was not possible to pair the populations in terms of gender. Instead, the results were analyzed with an adjusted model, including man characteristics as cofounders. We found that the mtDNAcn of the thyroid patients was significantly lower than that measured for the control group (p = 0.01). Furthermore the mtDNAcn of the benign group was significantly lower than that measured in the control group (p = 0.0001). A similar significant difference was found between the thyroiditis group and the control group (p = 0.005).

It was observed that mtDNAcn in the malignant group was significantly higher than that measured in the benign group (p = 0.004), which would indicate that it may be used as a diagnostic and therapeutic marker in thyroid diseases.