Genetic screening of solute carrier family 5 member 5 (SLC5A5) gene in Chinese Han congenital hypothyroidism patients with goiter

Objective: SLC5A5 mutations can cause thyroid dyshormonogenesis (an autosomal recessive metabolic disease) and account for approximately 10%-15% of congenital hypothyroidism (CH). In this study, we aimed to investigate the occurrence of SLC5A5 mutations in CH with goiter patients and to explore the spectrum of phenotypes arising from SLC5A5 mutations in Shandong province, China. Methods: Blood samples were collected from 110 Chinese CH with goiter patients, and genomic DNA was extracted from peripheral blood leukocytes. All 15 coding exons and exon-intron boundaries of SLC5A5 were amplified by polymerase chain reaction (PCR) and analyzed by direct sequencing. Results: Although pathogenic mutations in SLC5A5 were not identified, two rare SLC5A5 variants (A514S and R569W) were detected in non-consanguineous families. In addition, six polymorphisms (IVS5-51, IVS6+11, IVS8+22, IVS14-8, IVS14+22 and IVS14+28) were found. Conclusion: Our study revealed the rate of SLC5A5 mutation is low in CH with goiter patients in China. Two rare variants were identified in this study; however, further studies are needed to determine whether these variants may alter function and whether these patients have other reasons for CH.