先天性甲状腺功能减退症患儿双氧化酶1基因突变研究

Screening of double oxide enzyme mutations in patients with congenital hypothyroidism

目的研究山东地区先天性甲状腺功能减退症(CH)伴甲状腺肿大患儿双氧化酶1(DUOX1)基因突变类型及特点,为CH的诊断及基因治疗提供理论依据。方法选取43例经新生儿筛查确诊为CH伴甲状腺肿大患儿及100例正常对照新生儿,提取CH患儿及正常新生儿外周血基因组DNA,采用聚合酶链式反应(PCR)扩增及一代测序法(Sanger测序法),对DUOX1基因全部外显子进行基因突变检测,结合测序结果及生物信息学数据,分析DUOX1基因是否存在突变,并对发现的单核苷酸多态性(SNP)位点的基因频率进行χ2检验。结果在43例CH伴甲状腺肿大患儿及100例正常对照新生儿中,均未发现DUOX1基因突变。但在外显子区发现了2个SNP位点(rs16939752,c.3076T>C;rs1706804,c.3228A>G),前者为错义突变(Cys→Arg),后者为同义突变(Thr→Thr);内含子区发现了1个SNP位点(rs2020216,IVS8+129C>T)。经统计,本文实验组患儿与正常对照组新生儿SNP的基因频率比较,差异无统计学意义(P>0.05)。结论山东地区CH伴甲状腺肿大患儿中,DUOX1基因突变率低,可能不是该地区CH伴甲状腺肿大的主要病因。

Objective To study the types and characteristics of double oxide enzyme （DUOX1） mutation in patients with congenital hypothyroidism （CH） and thyroid goiter from Shandong province,and provide theoretical basis for the diagnosis and treatment of CH. Methods Totally 100 healthy individuals and 43 cases of patients who were diagnosed as congenital hypothyroidism （CH） were extracted their genomic DNA from peripheral blood and thyroid goiter in neonatal screening in Shandong Province. All the exons of DUOX1 were amplified by polymerase chain reaction （PCR） and direct se- quencing （Sanger sequencing）,DUOX1 gene was analysed whether there was mutation combining with the results of DNA sequencing and bioinformatics analysis,and χ^2 test was used. Results No DUOX1 gene mutation was found in 43 cases of CH with thyroid goiter patients and 100 healthy individuals enrolled according to the sequencing results and bioinformatics analysis,however,two SNPs were found （rs16939752, c. 3076T〉C; rs1706804, e. 3228A〉G） in exon region, the former was a missense mutation （Cys--~Arg） ,the latter was a synonymous mutation （Thr→Thr） ; one SNP was found （rs2020216, IVS8＋129C→T） in intron region. There was no significant difference between the SNP rate in CH patients and controls（P〉0.05）. Conclusion The DUOX1 gene mutation rate is very low which may not be the main factor leading to the congenital hypothyroidism with thyroid goiter in Shandong province,China.