familial goiter

(redirected from organification defect)

fa·mil·i·al goi·ter

a group of heritable thyroid disorders in which goiter is commonly apparent first during childhood; often associated with skeletal and/or mental retardation, and with other signs of hypothyroidism that may develop with age. Various types of familial goiter have been identified: iodide transport defect [MIM*274400]; of autosomal recessive inheritance caused by mutation in the sodium iodide symporter gene (SLC5A5) on 19p, in which the gland is unable to concentrate iodide; organification defect [MIM*274500 and *274600], in which the iodination of tyrosine is defective; Pendred syndrome [MIM*274600]; autosomal recessive inheritance caused by mutation in the Pendred syndrome gene (PDS) on 7q; associated with hearing loss; coupling defect [MIM*274700], in which cretinism results from defective coupling of iodotyrosines to form iodothyronines; iodotyrosine deiodinase defect [MIM*274800], in which deiodination of iodotyrosine is defective, considerable glandular loss of these hormonal precursors occurs, and cretinism may be present; plasma iodoprotein disorder [MIM*274900], in which an abnormal iodinated serum protein that is insoluble in acidic butanol is present; and hereditary hyperthyroidism.

fa·mil·i·al goi·ter

(fă-mil'ē-ăl goy'tĕr)
A group of heritable thyroid disorders in which goiter is commonly apparent first during childhood; often associated with skeletal or mental retardation, and with other signs of hypothyroidism that may develop with age.

fa·mil·i·al goi·ter

(fă-mil'ē-ăl goy'tĕr)
Group of heritable thyroid disorders in which goiter is commonly apparent first during childhood; often associated with skeletal and/or mental retardation, and with other signs of hypothyroidism that may develop with age.
References in periodicals archive ?
Clinically, a perchlorate discharge test in most TPO gene mutation patients will demonstrate the pattern of total iodide organification defect (18).
Mutation analysis of thyroid peroxidase gene in Chinese patients with total iodide organification defect: identification of five novel mutations.
High prevalence of a novel mutation (2268 insT) of the thyroid peroxidase gene in Taiwanese patients with total iodide organification defect, and evidence for a founder effect.
(10) Most patients with Pendred syndrome remain euthyroid, as dietary iodine intake is usually sufficient to compensate for the iodide organification defect. (10)
Currently, the procedure used to assess organification defect of the thyroid gland, called the thiocyanate or perchlorate discharge test, is to give the patient radioiodide followed a few hours later by an oral dose of 1 g potassium thiocyanate or 1 g of potassium perchlorate.
The advantages of the Triple Test procedure over the currently used thiocyanate (10) and perchlorate (11) discharge test to identify organification defect is that the Triple Test will obviate the need to inject radioiodide into the patient followed by administration of these iodine uptake inhibitors.
"Deficient cytochrome [b.sub.5] reductase activity in nontoxic goiter with iodide organification defect." Metabolism, 1975; 24(10):1103-1113.
In the present study, screening by single-strand conformational polymorphism (SSCP) and direct sequencing analysis of the DUOX2 gene revealed 3 previously unreported mutations and 1 previously reported mutation in 2 unrelated families with congenital goiter and iodide organification defect, constituting 2 compound heterozygous mutations (p.Q36H/p.5965fsX994 and p.G418fsX482/g.IV5192A>C).
We studied 17 selected unrelated patients with iodide organification defect (perchlorate discharge test [greater than or equal to]30%) from an original cohort of 40 patients with congenital goitrous hypothyroidism at screening.
Intake of perchlorate from a contaminated source may cause discharge of iodide from the thyrocyte, further exacerbating the organification defect, with resulting decrease of TH synthesis.
TPO defects are believed to be among the most frequent causes of abnormalities in thyroid iodide organification defect causing goitrous CH.
Twelve patients (36%) were diagnosed with dyshormonogenesis, which consisted of an organification defect in all but one patient.