Iodide Transport Defect: Functional Characterization of a Novel Mutation in the Na
/I Symporter 5
-Untranslated Region in a Patient with Congenital Hypothyroidism

JUAN PABLO NICOLA, MAGALÍ NAZAR, CAROLINE SERRANO-NASCIMENTO, FRANCEMILSON GOULART-SILVA, GABRIELA SOBRERO, GRACIELA TESTA, MARIA TEREZA NUNES, LILIANA MUÑOZ, MIRTA MIRAS, AND ANA MARÍA MASINI-REPISO

ENDOCRINE SOC

Lugar: New York; Año: 2011 vol. 96 p. 100 - 100

ontext: Iodide transport defect (ITD) is an autosomal recessive disorder caused by impaired Na/I sym- porter(NIS)-mediatedactiveiodideaccumulationintothyroidfollicularcells.Clinicalmanifestationscom- priseavariabledegreeofcongenitalhypothyroidismandgoiter,andlowtoabsentradioiodideuptake,as determined by thyroid scintigraphy. Hereditary molecular defects in NIS have been shown to cause ITD. Objective: Our objective was to perform molecular studies on NIS in a patient with congenital hypothyroidism presenting a clinical ITD phenotype. Design:ThegenomicDNAencodingNISwassequenced,andaninvitrofunctionalstudyofanewly identified NIS mutation was performed. Results: The analysis revealed the presence of an undescribed homozygous C to T transition at nucle- otide 54 (54CT) located in the 5-untranslated region in the NIS sequence. Functional studies in vitro demonstrated that the mutation was associated with a substantial decrease in iodide uptake whentransfectedintoCos-7cells.Themutationsev