论文部分内容阅读
目的 明确正常人促甲状腺素受体 (hTSHR)膜外区的基因序列及了解甲状腺疾病患者hTSHR膜外区基因突变的性质和特点。方法 从手术切除的甲状腺组织中提取总核糖核酸 (RNA) ,运用逆转录 聚合酶链反应 (RT PCR)扩增出全长的hTSHR膜外区基因。对 4例正常引产胎儿、12例Graves病、4例桥本甲状腺炎和 11例结节性甲状腺肿患者的甲状腺组织hTSHR膜外区基因进行序列分析。结果 得到 4例正常人的hTSHR膜外区基因序列。 2 7例甲状腺疾病患者的hTSHR膜外区基因序列与正常人的hTSHR序列完全一致 ,未发现有基因突变或多态性现象。但第 6 6 1位核苷酸与正常人hTSHR基因一样存在碱基替代现象。在正常人中 3例为胸腺嘧啶“T” ,1例为胞嘧啶“C” ;2 7例患者中 ,17例为“T” ,10例为“C”。但其组成的密码子由于遗传密码的简并性 ,所编码的氨基酸是相同的 ,故并不会造成hTSHR氨基酸组成的改变。结论 hTSHR膜外区基因突变可能不是该研究中甲状腺疾病的主要致病因素 ,其分子水平发病机制尚需进一步研究。
OBJECTIVE: To determine the gene sequence of the extracellular domain of thyrotropin-receptor (hTSHR) and to investigate the nature and characteristics of the gene mutation in hTSHR extracellular domain in patients with thyroid disease. Methods Total RNA was extracted from surgically excised thyroid tissue and the full-length hTSHR membrane extracellular region was amplified by reverse transcription-polymerase chain reaction (RT-PCR). Sequence analysis of hTSHR gene outside the thyroid tissue of 4 normal fetus fetus, 12 Graves’ disease, 4 Hashimoto’s thyroiditis and 11 nodular goiter. Results Four hTSHR gene sequences were obtained. Twenty-seven patients with thyroid disease patients with hTSHR membrane outer region of the gene sequence and normal hTSHR sequence exactly the same, found no genetic mutations or polymorphisms. However, the 661th nucleotide has the same base substitution as the normal human hTSHR gene. Among the normal subjects, 3 were thymine “T” and 1 was cytosine “C”. Of the 27 patients, 17 were “T” and 10 were “C”. However, due to the degeneracy of the genetic code, the codons that make up the encoded amino acids are the same and therefore do not change the amino acid composition of hTSHR. Conclusion The mutation of hTSHR gene outside the membrane may not be the main causative factor of thyroid disease in this study. The molecular pathogenesis needs further study.