International Journal of Preventive Medicine (Int J Prev Med)2008-780241201207255762ENDepartment of Pediatrics, School of Medicine, Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, IranDivision of Genetics, School of Medicine, Pediatric Inherited Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, IranDepartment of Physiology and Applied Physiology Research Center, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranDepartment of Genetics, School of Basic Sciences, Institute of Biotechnology, School of Basic Sciences, Shahrekord University, Shahrekord, IranDepartment of Genetics, School of Basic Sciences, Shahrekord University, Shahrekord, IranGeneral Practitioner, Child Growth and Development Research Center, Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, IranDepartment of Pediatric Endocrinology, Endocrine and Metabolism Research Center, Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran2012070420120704<p><strong>Background: </strong>Considering the high prevalence of congenital hypothyroidism (CH) in Isfahan and its different etiologies in comparison with other countries, the high rate of parental consanguinity, and the role of <em>NIS </em>gene in permanent CH due to dyshormonogenesis, the aim of this study was to investigate the G395R mutation of the <em>NIS </em>gene in patients with permanent CH due to dyshormonogenesis.</p> <p><strong>Methods: </strong>In this case&ndash;control study, patients diagnosed with permanent CH due to dyshormonogenesis during CH screening program were selected. Venous blood sample was obtained to determine the G395R mutations of <em>NIS </em>gene using polymerase chain reaction (PCR) sequencing method.</p> <p><strong>Results: </strong>In this study, 35 CH patients with permanent CH due to dyshormonogenesis and 35 neonates with normal screening results as a control group were studied. We did not find any changes of the mentioned mutation of <em>NIS </em>gene in the patients&rsquo; group.</p> <p><strong>Conclusion: </strong>Considering the findings of the current study, it seems that further studies with larger sample size and with consideration of other gene mutations such as pendrin and thyroglobulin are needed for more accurate conclusion.</p> <strong>Keywords: </strong>Congenital hypothyroidism, dyshormonogenesis, G395R, mutation, sodium/iodide symporter (<em>NIS</em>) genehttp://ijpm.mui.ac.ir/index.php/ijpm/article/view/786http://ijpm.mui.ac.ir/index.php/ijpm/article/download/786/774