先天性甲减患儿的甲状腺过氧化物酶基因突变研究

目的:研究甲状腺过氧化物酶基因(TPO)在中国先天性甲状腺功能减退症(CH)患儿中的突变及其家系遗传规律。方法:收集140例CH患儿及部分家系,提取外周血DNA,采用靶向测序的方法检测患者TPO基因的突变情况,设计引物扩增TPO基因的各个外显子区以及外显子内含子的交界区,用二代测序技术检测TPO基因的突变且进行一代测序验证,同时对其中两例携带有TPO基因复合杂合突变的患儿的父母进行一代测序验证。结果:140名先天性甲减患儿中,13例病人携带12个不同的TPO基因突变位点(R189Q、C269S、W428R、A430E、A433P、A489T、V748M、C756fs、E799D、G860R、P883S、Q913fs),其中有一个位点为热点突变(6个病人携带C756fs),三个突变为新发现的位点(C269S、A430E、E799D)。结论:TPO基因在中国先天性甲减患儿中的突变率较高,遗传模式为常染色体隐性遗传。

Identifying the TPO mutations from Patients with Congenital Hypothyroidism

ABSTRACT Objective: This study aimed to identify the thyroid peroxidase (TPO) gene mutations in 140 cases of Chinese patients with congenital hypothyroidism (CHT) and the inherited characteristics. Methods: Genomic DNA was extracted from the peripheral blood of 140 Chinese CHT, Access Array target sequencing was used to amplified all the exons and exon-intron boundaries of TPO and the next sequencing was used to perform deep sequencing of the amplicon libraries. Sanger sequencing was conducted among the parents of some CH patients with TPO mutations. Meanwhile, the parents of two compound heterozygotes with TPO mutations were tested by Sanger sequencing. Results: Among 140 patients with CH, 12 distinct TPO mutations were identified in 13 patients (R189Q, C269S, W428R, A430E, A433P, A489T, V748M, C756fs, E799D, G860R, P883S, Q913fs). Among these 12 mutation sites, 2 were hotspot mutations (C756fs were carried by 6 patients), 3 were novel mutations (C269S, A430E and E799D). Conclusion: High frequency mutation in TPO was detected in Chinese patients with CH, two pedigrees indicated TPO mutations inherited in an autosomal recessive fashion.