Disease-associated variants of either subunit of KATP, KCNJ11 and ABCC8, can result in a channel that is "stuck open", rendering the β cell unable to secrete insulin in response to high blood glucose. Children born with disease-associated KATP variants often have intrauterine growth restriction and resulting low birthweight. Similarly, the second most common cause of permanent neonatal diabetes is alterations to the gene that encodes insulin. Mutations associated with neonatal diabetes tend to cause misfolding of the insulin protein; misfolded insulin accumulates in the endoplasmic reticulum (ER), leading to ER stress and β-cell death.Most transient neonatal diabetes is caused by the over-expression of a cluster of genes on chromosome 6, a region called 6q24. Over-expression of 6q24 is often caused by anomylous epigenetic regulation of the locus. The copy of 6q24 inherited from ones father normally has much higher gene expression than the copy inherited from ones mother. Therefore, inheriting two copies of the gene region from ones father (either through uniparental disomy, or receiving two copies from ones father in addition to the copy from ones mother) commonly results in over-expression of the locus. Alternatively, inheriting a maternal copy of 6q24 with defective DNA methylation can result in similar over-expression of the locus.Variants in several other genes can cause neonatal diabetes, though these cases are much rarer. Genetic changes that disable the transcription factors CNOT1, GATA4, GATA6, PDX1, PTF1A, or RFX6 – all involved in the development of the pancreas – result in a shrunken or missing pancreas.
Thyrotoxicosis factitia (alimentary thyrotoxicosis, exogenous thyrotoxicosis) refers to a condition of thyrotoxicosis caused by the ingestion of exogenous thyroid hormone. It can be the result of mistaken ingestion of excess drug, such as levothyroxine and triiodothyronine, or as a symptom of Munchausen syndrome. It is an uncommon form of hyperthyroidism. Patients present with hyperthyroidism and may be mistaken for Graves’ disease, if TSH receptor positive, or thyroiditis because of absent uptake on a thyroid radionuclide uptake scan due to suppression of thyroid function by exogenous thyroid hormones. Ingestion of thyroid hormone also suppresses thyroglobulin levels helping to differentiate thyrotoxicosis factitia from other causes of hyperthyroidism, in which serum thyroglobulin is elevated. Caution, however, should be exercised in interpreting thyroglobulin results without thyroglobulin antibodies, since thyroglobulin antibodies commonly interfere in thyroglobulin immunoassays causing false positive and negative results which may lead to clinical misdirection. In such cases, increased faecal thyroxine levels in thyrotoxicosis factitia may help differentiate it from other causes of hyperthyroidism. See also
Foodborne illness
Liothyronine

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