DUOX2基因突变引起先天性甲状腺功能减低伴甲状腺肿大的研究

目的研究先天性甲状腺功能减退(CH)患者DUOX2基因突变情况及基因型与表现型的关系。方法对10例CH患者伴甲状腺肿大的DUOX2基因的全部外显子进行基因突变筛查。结果在1例CH患儿中发现DUOX2基因单个等位基因的杂合性突变,为第17外显子cDNA的2101位点发生了C>T的突变(c.C2101T),导致第701密码子精氨酸变为终止密码(p.R701X)。结论我们的结果证实了DUOX2基因单个等位基因突变可引起CH伴甲状腺肿大。     

先天性甲状腺功能减退症患儿FOXE1基因突变研究

目的研究山东地区先天性甲状腺功能减退症(CH)伴甲状腺发育不全患儿转录因子2(FOXE1)基因突变类型及特点,为CH的诊断及治疗提供理论依据。方法选取60例CH伴甲状腺发育不全患儿,提取外周静脉血基因组DNA,采用PCR扩增与直接测序技术,对FOXE1基因全部编码序列进行突变筛查。结果在60例先天性甲状腺功能减退症伴甲状腺发育不全患者外显子测序中未发现基因突变位点,在6例患者中发现1个单核苷酸多态性(SNP)位点(rs755282859,c.483GA),变异频率为10%。结论 FOXE1基因突变率较低,可能不是山东地区CH伴甲状腺发育不全的主要原因。     

先天性甲状腺功能减退症伴甲状腺肿大患儿DUOX2基因突变研究

目的先天性甲状腺功能减退(CH)是小儿最常见内分泌疾病之一。在已经发现的多种由于甲状腺激素合成与分泌的酶基因突变而导致CH中,以常染色体隐性方式遗传的DUOX2基因突变越来越受到国外学者关注,然而目前国内却没有该方面研究。研究中国人群CH患者常见的DUOX2基因突变类型和特点,不仅有利于CH患者的早期诊断或症状前诊断,而且有利于开展产前诊断,提高出生人口素质。方法本研究利用来自8例甲状腺肿大CH患者为研究对象,对DUOX2基因的全部外显子进行基因突变筛查,结合测序验证及生物信息学分析,研究中国人群CH患者常见的DUOX2基因突变类型和特点。结果 8例甲状腺肿大CH患者均没有发现DUOX2基因致病突变。但是在这些样本中,检测到3个氨基酸的改变,经过生物信息学分析后发现这些氨基酸的改变均位于DUOX2基因的非保守性位点,为新的多态性的改变,而不是引起CH的致病突变。在样本2中,DUOX2基因第三外显子中脯氨酸被亮氨酸取代,即DUOX2 c227 C>T(P76L),样本5中DUOX2基因第十三外显子发生同义突变,即DUOX2 c1621 C>A(R541R),样本6中,DUOX2基因第二十六外显子中赖氨酸被精氨酸取代,即DUOX2 c3532 A>G(K1178R)。结论 DUOX2基因在中国先天性甲状腺功能减退症伴甲状腺肿大的患儿中突变率极低,并不是引起伴甲状腺肿大的CH的常见致病基因。     

青岛地区先天性心脏病患儿GATA-4基因突变的研究

目的研究山东省青岛地区先天性心脏病患儿GATA4基因突变情况。方法采用PCR直接测序技术对70例先天性心脏病患儿GATA-4基因的全部外显子进行基因突变筛查。结果在1例先天性心脏病室间隔缺损患儿中发现GA-TA4基因的杂合性突变,为第4外显子cDNA的886位点发生G〉A的杂合突变（c.886G〉A）,结果导致其编码蛋白的第296密码子由甘氨酸突变为丝氨酸（p.G296S）,为错义突变。结论在山东省青岛地区先天性心脏病患儿中发现了GATA-4基因的p.G296S突变,该突变可能导致先天性心脏病。     

109例先天性甲状腺功能减低症患儿甲状腺过氧化物酶基因突变检测

目的对109例先天性甲状腺功能减低症患儿进行甲状腺过氧化物酶基因(TPO)基因突变研究。方法对109例先天性甲状腺功能减低症患儿采样并提取DNA,用wafergen验证检测患儿TPO基因突变。PCR扩增患儿TPO基因各外显子、外显子-内含子交界区以及3′端和5′端非翻译区,以DNA测序技术检测TPO基因突变。结果 7例CH患儿存在7种TPO基因突变,分别为c.1082GT[p.Arg361Leu]、c.1117GT[p.Ala373Ser]、c.2012GT[p.Trp671Leu]、c.2268ins T[p.Glu757fs]、c.1471CT[p.Arg491Cys]、c.2173AC[p.Thr725Pro]、c.2647CT[p.Pro883Ser]。结论中国人群先天性甲状腺功能减低症患儿存在较高频率的甲状腺过氧化物酶基因突变。     

山东地区先天性心脏病患者CFC1基因突变研究

目的对山东地区126例先天性心脏病患者进行CFC1基因突变筛查,阐明CFC1基因突变类型和特点,为先天性心脏病患者的基因诊断和基因治疗提供理论依据。方法．从126例先天性心脏病患者外周血白细胞中提取基因组DNA,进行PCR扩增CFC1第2和3外显子,对PCR产物进行直接测序分析。结果在126例先天性心脏病患者患儿的CFC1基因第2、3外显子测序中,均未发现基因突变。结论CFC1基因突变率低,可能不是山东地区先天性心脏病患儿的主要致病基因。     

一个白化病家系的TYR基因突变分析北大核心CSCD

目的对1个白化病家系的TYR基因进行突变检测,为遗传咨询和产前诊断提供参考。方法应用PCR技术扩增TYR基因的全部外显子区和外显子-内含子交界区序列,进行DNA测序。结果测序结果显示家系2例患者的TYR基因第2外显子存在c．896G〉A（p．Arg299His）纯合突变,7名表型正常的家系成员的TYR基因第2外显子存在c．896G〉A（Arg299His）杂合突变,7名家系成员和4名正常对照者则均未检测到该突变。结论TYR基因第2外显子c．896G〉A（p．R299H）突变应为该白化病家系的致病原因。     

中国山东地区先天性甲状腺功能减低症患者PAX8基因突变筛查研究

目的对中国山东地区先天性甲状腺功能减低症(简称甲低)患者PAX8第4外显子进行基因突变筛查,阐明中国山东地区甲低患者PAX8基因第4外显子突变特点。方法 453例标本来自山东甲状腺发育不全的先天性甲低患者,从外周血白细胞中提取全基因组DNA扩增PAX8第4外显子,对PCR产物进行直接测序分析。结果分析453例PAX8第4外显子测序结果未发现突变,但在1例患者第4内含子发现1个IVS4+83 T>C突变,在第4内含子区发现1个SNP位点(rs74370449,IVS4+101 G/A,变异频率为8.9%)。结论 PAX8基因第4外显子突变率在中国山东地区甲低患者中极低,PAX8第4内含子的突变可能与先天性甲低相关。     

三个先天性遗传性白内障家系的致病基因突变分析CSCD

目的明确3个有家族史的先天性白内障家系的致病基因及突变类型,为家系的遗传咨询及产前诊断提供依据。 方法应用外显子组结合目标区域捕获测序芯片对先证者进行突变基因及突变位点捕获,Sanger测序对家系成员进行验证。结果家系1为多形性白内障,家系2为蓝点状白内障,家系3为珊瑚状白内障。3个家系的遗传方式均符合常染色体显性遗传。家系1患者均检测出CRYβB2基因c.463C〉T（p.Q155X）无义突变,家系2患者均检测出CRYGD基因c.43C〉T（ p．R14C）错义突变,家系3患者均检测出CRYGD基因c.70C〉A（p.P23T）错义突变;这些突变均表现为基因型与疾病共分离。结论家系1、2和3的致病性突变分别为CRYβB2基因c.463C〉T（p.Q155X）突变、CRYGD基因c.43C〉T（p.R14C）突变和CRYGD基因c.70C〉A（p.P23T）突变,本研究结果为家系的遗传咨询及产前诊断提供了依据.     

二例先天性肌强直的CLCNl基因突变研究

目的 探讨2例先天性肌强直患者的氯离子通道蛋白-1(chloride channcl 2,CLCN1)基因突变情况和临床特点.方法 收集福建地区1个先天性肌强直家系的先证者和1例散发性先天性肌强直患者的临床资料并进行综合分析.用PCR扩增患者CLCN1基因的全部外显子,通过直接测序检测突变的情况.结果 家系1先证者的CLCN1基因第8外显子存在c.1024 G>A的杂合性错义突变,散发性患者的CLCN1基因第11外显子发现了c.1292 C>T的杂合性错义突变.结论 先天性肌强直症临床表现缺乏特异性,CLCN1基因突变检测是确诊该病的有效方法.     

Mutations in the iodotyrosine deiodinase gene and hypothyroidism

DEHAL1 has been identified as the gene encoding iodotyrosine deiodinase in the thyroid, where it controls the reuse of iodide for thyroid hormone synthesis. We screened patients with hypothyroidism who had features suggestive of an iodotyrosine deiodinase defect for mutations in DEHAL1. Two missense mutations and a deletion of three base pairs were identified in four patients from three unrelated families; all the patients had a dramatic reduction of in vitro activity of iodotyrosine deiodinase. Patients had severe goitrous hypothyroidism, which was evident in infancy and childhood. Two patients had cognitive deficits due to late diagnosis and treatment. Thus, mutations in DEHAL1 led to a deficiency in iodotyrosine deiodinase in these patients. Because infants with DEHAL1 defects may have normal thyroid function at birth, they may be missed by neonatal screening programs for congenital hypothyroidism.     

Dyshormonogenetic goiter‐like changes in a child with congenital hypothyroidism and a euthyroid adult

Dyshormonogenetic goiter is a rare entity that presents in patients who typically have a history of congenital hypothyroidism, and generally arises from a genetic mutation compromising the production of functional thyroxine or thyroglobulin. Clinically, physical manifestations of goiter can result if left untreated. Histologically, the thyroid lesions usually show prominent bridging fibrosis, multiple thyroid nodules with different architectures, microfollicular arrangement, scant colloid, and enlarged vesicular or hyperchromatic nuclei. Cytologically, the features of the lesion are not distinguishable from follicular lesion and follicular neoplasm. We describe two patients exhibiting similar histological and cytological features resembling dyshormonogenetic goiter with cytologic misinterpretation as follicular neoplasm. One was a child with an established history of congenital hypothyroidism. The other was an adult euthyroid patient who presented with an associated parathyroid adenoma. These findings further affirm that cytologically and histologically, morphologic features associated with dyshormonogenetic goiter can also be found in patients without a history of congenital hypothyroidism. Diagn. Cytopathol. 2013;41:720–724. © 2013 Wiley Periodicals, Inc.     

A novel compound heterozygous mutation in the thyroglobulin gene resulting in congenital goitrous hypothyroidism with high serum triiodothyronine levels

Thyroglobulin abnormality is a rare cause of congenital hypothyroidism and only a limited number of mutations in the thyroglobulin gene have been reported. We analyzed the thyroglobulin gene in a patient with congenital goitrous hypothyroidism. This girl was identified with hyperthyrotropinemia in a neonatal mass-screening test. The patient had goiter, and her body weight gain was poor. Distal femoral epiphysis was absent on roentgenography. Her serum thyroxine level was low; however, her triiodothyronine level was high. Autoantibodies against triiodothyronine, thyroid peroxidase, and thyroglobulin were all negative. Her serum thyroglobulin level was undetectable. The thyroglobulin gene from the genomic DNA of the patient was analyzed by direct sequencing. Two novel heterozygous missense mutations, Cys1897Tyr (exon 31) and Arg2336Gln (exon 40), were found in the patient. The former mutation was derived from her mother, suggesting a compound heterozygous state. Normal triiodothyronine and low thyroxine concentrations are often observed in patients with thyroglobulin gene mutations. We considered that some patients with thyroglobulin abnormality might have high triiodothyronine levels. In cases of congenital goitrous hypothyroidism with normal-to-high triiodothyronine levels and low serum thyroglobulin levels, thyroglobulin abnormality should be considered.     

先天性甲状腺功能减低症一家系TPO基因突变分析

目的对一个有2例患者的先天性甲状腺功能减低症家系进行甲状腺过氧化物酶(TPO)基因突变研究。方法对该家系中4名成员采样并提取DNA,用PCR扩增先证者TPO基因各外显子、外显子-内含子交界区以及3’端和5’端非翻译区,以DNA测序技术检测基因突变,并与该家系中其他成员进行对照分析。结果先证者和其患同病的姐姐为TPO基因c.2268insT突变的纯合子,其父母均为此突变的杂合子。结论 TPO基因突变是中国人群先天性甲状腺功能减低症发生的原因之一。     

Identification of five novel inactivating mutations in the human thyroid peroxidase gene by denaturing gradient gel electrophoresis

Thyroid peroxidase (TPO) is the key enzyme in the synthesis of thyroid hormones. Defects in the TPOgene are reported to be the cause of congenital hypothyroidism due to a Total Iodide Organification Defect (TIOD). This type of defect, where iodide taken up by the thyroid gland cannot be oxidized and bound to protein, is the most common hereditary inborn error causing congenital hypothyroidism in the Netherlands. Denaturing Gradient Gel Electrophoresis (DGGE) of PCR amplified genomic DNA was used to screen for mutation in the TPO gene of TIOD patients from nine apparently unrelated families, and seven different mutations were detected. Three frameshift mutations were found: a 20 bp duplication in exon 2, a 4 bp duplication in exon 8, and an insertion of a single nucleotide (C) at pos. 2505 in exon 14. In addition, four single nucleotide substitutions were identified: one single-base, mutation resulted in a premature termination codon (C → T at pos. 1708 in exon 10), two single-base substitutions changed an amino acid in highly conserved regions of the gene (Tyr → Asp in exon 9 and Glu → Lys in exon 14). The fourth single-base mutation located at the exon 10/intron 10 border altered a conserved Gly into Ser and could also affect splicing. Nine TIOD patients from five families were compound heterozygotes and six patients from four families were homozygous for one of the mentioned mutations in the TPO gene. © 1995 Wiley-Liss, Inc.