Review Article
Pendred Syndrome and Role of Pendrin on Thyroid Physiology
Nada Mukhtar1
*
* 1 Corresponding author: Nada Mukhtar, Assistant Professor, Department of Biochemistry
and Molecular Biology, Napata College, Khartoum, Sudan.
Email: nadamukhtarha@gmail.com
Received: 20 September 2022
Accepted: 5 October 2022
Background: Pendred syndrome (PS) is an autosomal recessive disorder characterized by
sensorineural hearing impairment, presence of goiter, and a partial defect in iodide organification
(PIOD), which may be associated with insufficient thyroid hormone synthesis. Mutations in the
SLC26A4/PDS gene are found in patients with PS. Goiter development and developments of
hypothyroidism are variable and depend on nutritional iodide intake.
Moreover, PS may present with goiter, hypothyroidism, and a positive perchlorate test, a definite
etiologic diagnosis is impossible without molecular diagnosis in individuals who have a
concomitant hearing impairment.
Etiology: Pendred syndrome (OMIM 274600) occurs due to biallelic inactivating mutations in
the Pendrin gene (PDS/SLC26A4), which encodes Pendrinprotein. The SLC26A4 gene has been
mapped to chromosome 7q22.3 in 1996.
Epidemiology: The prevalence of Pendred syndrome has been estimated to be between 7.5 and
10 per 100,000 individuals. More importantly, Pendred syndrome accounts for to up to 10% of
hereditary deafness cases.
Pathophysiology: Pendrin is mainly expressed in tissues as diverse as the thyroid, the inner ear,
the kidney, airways, mammary gland, testis, placenta, endometrium and liver. The localization
and specific function of pendrin particularly in the thyroid gland, inner ear and kidney are well
described.
Keywords: Pendred, Thyroid, SLC26A4/PDS gene, hypothyroidism, recessive disorder
