目的：探讨Pax8基因在先天性甲状腺功能减低症(甲低)病因学中的地位。方法：对50例经内分泌专科门诊或新生儿筛查检出确诊的先天性甲状腺功能减低症患者，从外周血白细胞中提取基因组DNA，采用PCR-SSCP-DNA测序方法进行Pax8基因外显子2～9分析。结果：Pax8基因外显子2～9编码区未发现突变。结论：Pax8基因编码区的结构改变，在中国人甲低的病因学中可能不具有重要地位。

OBJECTIVE: To investigate the role of Pax8 in the pathogenesis of congenital hypothyrodism. METHODS: Genomic DNA was extracted from peripheral blood lymphocytes and PCR SSCP Direct DNA sequencing was applied to study exon 2～exon 9 of Pax8 gene in fifty patients who had been detected by neonatal screening or endocrinologists and diagnosed as having congenital hypothyroidism. RESULTS: No mutation was demonstrated in the encoding regions of Pax8 gene. CONCLUSIONS: Structural changes in Pax8 gene may not play an important role in pathogenesis of primary congenital hypothyroidism.