A Novel V59E Missense Mutation in the Sodium Iodide Symporter Gene in a Family with Iodide Transport Defect

Iodide transport defect results from the malfunction of iodide transporter (sodium iodide symporter [NIS]), and is characterized by low uptake of iodide into thyroid cells. Genetic analysis revealed that a T354P missense mutation causes iodide transport defect in the homozygous state and is a frequent mutation in the Japanese population. We recently reported three siblings with iodide transport defect harboring the T354P mutation in the heterozygous state. Here we report a novel V59E missense mutation associated with these siblings. The mutant protein showed low iodide transport activity.