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Reply to ‘Why the science on T3 and genomics is not settled’

Nature Reviews Endocrinology (2025)Cite this article

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I thank Lyons and Priestley for their comments (Lyons, G. & Priestley, J. Why the science on T3 and genomics is not settled. Nat. Rev. Endocrinol. https://doi.org/10.1038/s41574-025-01185-x (2025))1 on my recent World View article (Saunders, M. Liothyronine treatment for hypothyroidism — a patient’s view. Nat. Rev. Endocrinol. 21, 453–454 (2025))2, which raise some interesting points. In my view, the important question is not whether the science on DIO2 polymorphism is settled but what risks we run by prematurely, or mistakenly, dismissing its relevance.

The position of the British Thyroid Foundation (BTF) regarding the genomic tests for thyroid function that are available via private companies is unequivocal: “... these [genomic] tests are not offered by the NHS because they are unnecessary, a waste of money and the results are frequently meaningless”3. It is inaccurate to imply that the science around the DIO2 Thr92Ala polymorphism and thyroid genomics has stalled, or that it provides no meaningful clinical insight.

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References

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  1. East Sussex, UK

    Mary Saunders

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Saunders, M. Reply to ‘Why the science on T3 and genomics is not settled’. Nat Rev Endocrinol (2025). https://doi.org/10.1038/s41574-025-01186-w

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