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Context: Children with congenital hypothyroidism (CH) are at risk for suboptimal neurodevelopment., Objectives: To evaluate neurocognitive function and white matter microstructure in children with permanent or transient CH and to correlate these findings with disease severity., Design, Participants and Methods: A retrospective and prospective observational study was conducted in 39 children with permanent or transient CH, and in 39 healthy children. Cognitive function was assessed by Wechsler Intelligence Scale, Fourth Edition, and by other tests; the white matter microstructure was investigated by 3 Tesla magnetic resonance imaging., Results: Children with permanent CH have lower cognitive scores at a median age of 9.5 years than those with transient CH and controls. An IQ score between 71 and 84 was found in 28.6% of permanent CH and of <70 (P = 0.06) in 10.7%. The Processing Speed Index (PSI; P = 0.004), sustained visual attention (P = 0.02), reading speed (P = 0.0001), written calculations (P = 0.002), and numerical knowledge (P = 0.0001) were significantly lower than controls. Children born to mothers with Hashimoto's thyroiditis have significantly lower IQ values (P = 0.02), Working Memory Index (P = 0.03), and PSI (P = 0.02). Significantly lower IQ and Verbal Comprehension Index values were found in children with a family history of thyroid disorders (P = 0.004 and P = 0.009, respectively). In children with permanent CH, significant correlations between abnormalities in white matter microstructural, clinical, and cognitive measures were documented., Conclusions: These findings indicate that children with CH are at risk of neurocognitive impairment and white matter abnormalities despite timely and adequate treatment. The association between offspring cognitive vulnerability and maternal thyroid disorders requires careful consideration., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Thyroid hormones have important roles in growth, development and control of metabolism, and their dysregulation can lead to disease., Objectives: To identify genes contributing to hyperthyrotropinaemia., Design, Setting, Participants: Linkage and association analyses using 1258 individuals from three Alpine villages., Outcome Measures: The study applied two different upper limits of the reference range (URR) for serum thyroid stimulating hormone (TSH) values (TSH ≥4.6 mU/l and TSH >3.0 mU/l), along with normal or low fT4 (free thyroxine) values or thyroid medical treatment to define two groups of individuals for analysis: one hyperthyrotropinaemic or high-TSH (H-TSH) (TSH ≥4.6 mU/l) group; and a larger group (TSH >3.0 mU/l) called hyperthyrotropinaemic and upper reference range TSH (H+URR-TSH)., Results: Non-parametric genome-wide linkage analysis was performed on pedigrees generated from the two groups. Linkage analysis in the H+URR-TSH group revealed a significant peak on chromosome 3q28-q29 (LOD 3.34) and a suggestive linkage peak on chromosome 6q26-27 (LOD 2.66). Analysis in the smaller hyperthyrotropinaemic (H-TSH) group supported linkage to chromosome 6q26-27. Single SNP and gene based SNP association analyses under the linkage peaks identified the PDE10A and DACT2 genes as candidates at the chromosome 6 locus., Conclusions: PDE10A or DACT2 were identified as candidate genes contributing to hyperthyrotropinaemia (and possibly hypothyroidism) in this sample. Studies in additional populations support association of variants at this locus with TSH values, especially in the PDE10A gene. Genetic linkage in families with hyperthyrotropinaemia suggests the presence of functional variants that contribute to pathological disruption of the hypothalamus-pituitary-thyroid axis.

Thyroid dysfunction and autoimmunity have been reported during type I interferon therapy, namely interferon-alpha for chronic hepatitis or interferon-beta for multiple sclerosis. To define the frequency of thyroid dysfunction and autoimmunity during interferon-beta treatment, 156 multiple sclerosis patients were prospectively followed up by 18 centers for 1 yr after starting interferon-beta-1b treatment. Serial clinical assessments and tests of thyroid and liver function and antithyroid autoantibodies (all performed by the same centralized laboratory) were conducted every 3 months. TSH and antithyroid autoantibodies against human TG or thyroid microsomal antigens were measured by immunoradiometric methods; free T3 and T4 were measured by chromatographic assays. Longitudinal occurrence of thyroid or liver alterations or of autoantibodies was analyzed with the generalized estimating equations method, correcting for the correlation of repeated measurements of the same subject over time. Pretreatment comparison with a control group of 437 healthy blood donors did not show significant differences in the frequency of thyroid dysfunction or antithyroid autoantibody positivity. During interferon-beta treatment, the de novo frequency of thyroid alteration was 8.3%, that of liver alteration was 37.5%, and that of antithyroid autoantibody was 4.5%. Generalized estimating equations analysis demonstrated that the frequency of liver alteration significantly increased during treatment compared with the baseline value (odds ratio, 7.03; confidence interval, 2.49-19.9), whereas that of thyroid alteration or of antithyroid autoantibodies did not. The frequency of thyroid dysfunction during interferon-beta treatment showed random, nonsignificant changes over time and, in addition, was not correlated to antithyroid autoantibody positivity.

Autoimmune thyroid diseases (AITDs) are clustered in families, but the nature of this clustering is still poorly understood. One possible approach to the identification of genetic factors interacting with the AITDs is the study of the association between polymorphic markers and AITDs themselves. In the present study we have shown an association between an allele of a HindIII restriction fragment length polymorphism (EA beta H) intragenic to c-erbA beta, which codes for the thyroid hormone beta receptor, and Graves' disease. This polymorphism can be detected by PCR followed by digestion with the restriction enzyme HindIII. The allelic frequencies were analysed in a panel of DNAs extracted from a population of individuals affected by thyroid disease and originating from southern Italy. A control group (n = 120) from the same area was also analysed. The distribution of EA beta H alleles was significantly different (P < 0.001) in Graves' disease (n = 94) but not in autoimmune thyroiditis (n = 60), as compared with controls. Also the distribution of the EA beta H genotypes was significantly different in Graves' patients (P = 0.003), as compared with controls, the homozygous state EA beta H+/EA beta H+ being more frequent in Graves' patients than in all the other groups. We did not find any association between EA beta H genotypes and clinical parameters in Graves' patients, including eye signs, thyroid volume and level of TSH-binding inhibiting immunoglobulins. Our data support the idea that Graves' disease is a genetically distinct group within the AITDs.

Taste sensitivity to phenylthiocarbamide (PTC) using the Harris-Kalmus method was studied in 193 patients with thyroid disease and in a control sample of 311 individuals living in the Emilia area of Italy. The patients were classified according to the morphology of struma (mononodular, polynodular, diffuse) and to the toxic and nontoxic forms of goiter. Eighteen percent were nontasters in the control sample; 37.2% were nontasters in patients with polynodular goiter (toxic and nontoxic forms). Highly significant differences between the two groups were observed. The results obtained on this Italian sample agree with the conclusions of other studies.