title: Identification and characterization of novel PAX8 mutations in Congenital Hypothyroidism(CH) in a Chinese population.
abstract: OBJECTIVE
  Based on mutations in PAX8 is associated with thyroid dysgenesis. We aim to identify and characterize PAX8 mutations in a large cohort of congenital hypothyroidism(CH) from thyroid dysgenesis in Chinese population.
  
  
  METHODS
  We screened 453 unrelated Chinese patients with CH from thyroid dysgenesis for PAX8 mutations by sequencing the whole coding regions of PAX8 on genomic DNA isolated from blood. Cell transfection assays using various vector constructs and induced mutagenesis as well as electrophoretic mobility shift assays were used to investigate the effects of selected mutations on the transcribing and binding activities of PAX8 at the promoters of target genes for thyroglobulin (TG) and thyroperoxidase (TPO).
  
  
  RESULTS
  Five PAX8 mutations were found, yielding a mutation prevalence of 5/453 (1.1%). We selected two mutations in the critical paired domain of PAX8 and generated mutants D94N and G41V. We demonstrated G41V was unable to bind the specific sequence in the promoters of TG and TPO and activate them. D94N could bind to TG and TPO promoters and normally activate the TG promoter transcription but not the TPO promoter transcription. We also demonstrated a dominant negative role of the PAX8 mutants in impairing the function of the wild-type PAX8.
  
  
  CONCLUSIONS
  We for the first time documented the prevalence and characterized the function of PAX8 mutations in CH in Chinese population. The study specifically demonstrated the role of novel mutations D94N and G41V in impairing the function of PAX8, providing further evidence for genetic PAX8 defects as a disease mechanism in CH.
authors.affiliation: Prenatal Diagnosis Center, The Affiliated Hospital of Qingdao University, Qingdao, China.|Genetic Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China.
authors.forename: Shiguo
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medicine, Qingdao University, Qingdao, China.|National Research Institute for Family Planning, Beijing, China.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Neonatal Screening Center, Jinan Women & Children Medical Healthcare Center, Jinan, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zou
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Medicine, Qingdao University, Qingdao, China.
authors.forename: Yinlin
authors.initials: Y
authors.lastname: Ge
authors.affiliation: Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China.
authors.forename: Yangang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China.
authors.forename: Shengli
authors.initials: S
authors.lastname: Yan
authors.affiliation: National Research Institute for Family Planning, Beijing, China.|Graduate School, Peking Union Medical College, Beijing, China.|World Health Organization Collaborating Centre for Research in Human Reproduction, Beijing, China.
authors.forename: Hongfei
authors.initials: H
authors.lastname: Xia
authors.affiliation: Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China.|Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, The Johns Hopkins University School of Medicine, USA.
authors.forename: Mingzhao
authors.initials: M
authors.lastname: Xing
mesh_terms: D044466:Asian People / Q000235:genetics; D001324:Autoantigens / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D014408:Biomarkers, Tumor / Q000235:genetics* / Q000378:metabolism; D002675:Child, Preschool; D003409:Congenital Hypothyroidism / Q000175:diagnosis / Q000208:ethnology / Q000235:genetics* / Q000378:metabolism; D004252:DNA Mutational Analysis; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006367:HeLa Cells; D006801:Humans; D007223:Infant; D007453:Iodide Peroxidase / Q000235:genetics / Q000378:metabolism; D033862:Iron-Binding Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D009154:Mutation; D000072636:PAX8 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D011237:Predictive Value of Tests; D011401:Promoter Regions, Genetic; D012307:Risk Factors; D013954:Thyroglobulin / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D001324:Autoantigens; D014408:Biomarkers, Tumor; D033862:Iron-Binding Proteins; D000072636:PAX8 Transcription Factor; C083325:PAX8 protein, human; D013954:Thyroglobulin; C056658:TPO protein, human; D007453:Iodide Peroxidase
keywords: PAX8 mutation; congenital hypothyroidism; paired box transcription factor; thyroid dysgenesis; thyroid gene