雄激素受体基因新突变引起的完全型雄激素不敏感综合征

目的 对1例完全型雄激素不敏感综合征(complete androgen insensitivity syndrom,CAIS)的雄激素受体(androgen receptor,AR)基因进行分析,寻找致病突变.方法 提取外周血全基因组DNA,扩增位于X染色体上的AR基因所有8个外显子及邻近外显子与内含子之间的剪切位点DNA序列,对扩增片段直接进行DNA序列测定,与基因库中的序列进行比对.结果 该病例AR基因第1外显子的441位密码子发生无义突变(GAA→TAA),由编码谷氨酸(Glu)变为终止密码,导致雄激素受体蛋白翻译至441位时终止,产生没有功能的氨基酸多肽残段.结论 Glu441stop(GAA→TAA)是一种导致CAIS的AR基因新的突变方式,之前在世界范围内均未见报道,丰富了AR基因突变谱,增加对CAIS发病机制的了解.     

雄激素受体基因新突变引起的完全型雄激素不敏感综合征

目的 对1例完全型雄激素不敏感综合征(complete androgen insensitivity syndrom,CAIS)的雄激素受体(androgen receptor,AR)基因进行分析,寻找致病突变.方法 提取外周血全基因组DNA,扩增位于X染色体上的AR基因所有8个外显子及邻近外显子与内含子之间的剪切位点DNA序列,对扩增片段直接进行DNA序列测定,与基因库中的序列进行比对.结果 该病例AR基因第1外显子的441位密码子发生无义突变(GAA→TAA),由编码谷氨酸(Glu)变为终止密码,导致雄激素受体蛋白翻译至441位时终止,产生没有功能的氨基酸多肽残段.结论 Glu441stop(GAA→TAA)是一种导致CAIS的AR基因新的突变方式,之前在世界范围内均未见报道,丰富了AR基因突变谱,增加对CAIS发病机制的了解.     

完全型雄激素不敏感综合征雄激素受体基因突变分析

目的 对完全型雄激素不敏感综合征一家系雄激素受体(androgen receptor,AR)基因进行突变检测;并对发现突变的基因进行分析.方法 应用PCR扩增、DNA序列测定等技术分析所有AR基因外显子及其邻近DNA序列片段;应用核苷酸内切酶诊断方法观察其是否存在于正常人群;应用跨物种比对方法探讨突变所在位置的保守性.结果 3例患者AR基因第4外显子均发生E681D(GAG→GAT)错义突变,患者母亲为此突变杂合子携带者;患者父亲未见异常;正常人群未发现AR基因E681D突变;681位谷氨酸在不同物种间高度保守.结论 AR基因E681D(GAG→GAT)突变可能是导致完全型雄激素不敏感综合征新的突变方式.     

完全型雄激素不敏感综合征雄激素受体基因突变的鉴定与分析

目的 对l例完全型雄激素不敏感综合征(complete androgen insensitivity syndrome,CAIS)患者的雄激素受体(androgen receptor,AR)基因进行分析,寻找潜在的突变位点,并进一步分析其发病原因.方法 提取患者外周血全基因组DNA,扩增位于X染色体AR基因8个外显子及邻近外显子与内含子剪切位点DNA序列,对扩增产物直接进行DNA序列测定,与GenBank中的基因序列进行比对.结果 该患者AR基因在第6外显子核苷酸序列3507位点缺失一个碱基C而引起移码突变,致使在第808位密码子出现终止密码子(TGA)使得翻译提前终止形成截短的雄激素受体蛋白.该突变可能诱导雄激素受体结合能力发生功能上的变异,导致CAIS的发生.结论 AR基因第6外显子核苷酸序列3507位点缺失碱基C引起的移码突变是一种导致CAIS新的基因突变方式,该研究丰富了AR基因突变谱,为了解CAIS的发病机制提供了新的依据.     

雄激素受体基因剪接受点突变G3346→T引起一例完全型雄激素不敏感综合征

目的－探讨完全型雄素不敏感综合征（complete androgen insensitivity syndrome,cAIS)发病的分子机理,并研究雄激素受体（androgen receptor,AR)结构,功能及其与临床表现的关系。方法 用银染聚合酶链反应－单链构象多态性（polymerase chain reaction-single strand conformation polymorphism,PCR-SSCP)及PCR产物直接测序的方法,对1例完全型AIS患者AR基因外显子B－H分别进行了研究。结果 外显子F片段在SSCP分析时有泳动变位,经测序,突变发生在内含子5与外显子F交界处G^3346→T,结论 为首例发现的AR基因剪接受点突变,GU－AG的高度保守对于维持AR的正常功能非常重要。     

用长链RT-PCR技术分析一个完全型雄激素不敏感综合征家系 AR基因的突变

目的 分析一例完全型雄激素不敏感综合征(complete androgen insensitivity syndrome,CAIS)患者及其家系成员雄激素受体(androgen receptor, AR)基因的潜在突变。 方法 提取患者及其家系成员的外周血基因组DNA和总RNA,应用PCR技术扩增X染色体上 AR基因的7个外显子,对产物直接进行DNA测序,寻找突变位点;应用PCR-限制性片段长度多态性方法分析相应的基因组片段,进一步确证 AR基因的突变位点;用逆转录PCR扩增 AR基因,再次验证其突变位点。 结果 发现患者及其舅舅 AR基因第7外显子的第2880个核苷酸G被A替换,引起错义突变,导致第840位密码子CGT突变为CAT,即精氨酸被组氨酸替代。该突变可能引起雄激素受体结合能力的变化,导致CAIS。患者母亲一条 AR等位基因的第840位密码子亦存在CGT→CAT改变,另一条等位基因则未发现突变。 结论 AR基因第7外显子核苷酸序列2880位点碱基G引起的错义突变很可能是引起CAIS的原因。应用长链RT-PCR技术扩增 AR基因可为CAIS的分子诊断提供新的方法。     

一种导致完全性雄激素不敏感综合征的AR基因移码突变的鉴定

目的 对1个男性假两性畸形完全性雄激素不敏感综合征的家系雄激素受体(androgen receptor,AR)基因进行突变检测,并分析其致病原因.方法 用PCR扩增及DNA测序等技术分析男性假两性畸形先证者候选基因AR的外显子及外显子内含子接头序列,根据检测到的突变位点情况,检测患者及其家系其他成员的相应DNA区段的碱基序列.结果 先证者及其家庭成员共3例患者均为AR基因1910delA的移码突变.其母亲为AR基因突变杂合子,是此疾病的携带者.该突变导致AR基因的N637I(AAU→AUC)、L638*(CTG→TGA)改变,导致AR蛋白283个氨基酸的截短.正常人群未发现该移码突变,该突变尚未见文献报道.结论 基因水平确定了该家系为AR基因突变引起的完全性雄激素不敏感综合征男性假两性畸形家系,同时发现了1种AR基因病理性新突变.     

雄激素受体异常与雄激素不敏感综合征

雄激素受体异常与雄激素不敏感综合征田秦杰，黄尚志，葛秦生雄激素不敏感综合征（ａｎｄｒｏｇｅｎｉｎｓｅｎｓｉｔｉｖｉｔｙｓｙｎｄｒｏｍｅ，ＡＩＳ）是一种单基因突变所致的性发育表型异常，其核型为４６，ＸＹ，性腺为睾丸，睾酮分泌正常，由于雄激素的正常效应全...     

完全型雄激素不敏感综合征一家系的遗传学分析

目的 报道一个完全型雄激素不敏感综合征家系。 方法 对一例表现为原发闭经和处女膜先天缺失的16岁女孩及其家系进行临床、内分泌和遗传学分析。 结果 先证者睾酮8.19 ng/mL,高于女性正常参考值,外周血染色体分析发现先证者及其小姨均为46,XY核型,FISH检测 SRY信号阳性, AR基因检测出c.1605C>G纯合突变,母亲为杂合子。而 SRY、NR5A1(SF1)、DHH、DAX1、WNT4等基因则未发现突变。确诊为完全型雄激素不敏感综合征。 结论 对性发育不良患者的准确诊断有赖于医生对临床症状和致病基因的清晰掌握。     

AR基因新变异致完全型雄激素不敏感综合征一个家系的遗传学分析及产前诊断

目的 探讨1个完全型雄激素不敏感综合征(CAIS)家系的临床与分子遗传学特征。 方法 选取2019年至2021年于天津医科大学总医院就诊的1个CAIS家系为研究对象。收集先证者相关临床资料,采集先证者及其家系成员外周血样,对先证者进行染色体核型分析、性别决定基因( SRY)检测及高通量测序(NGS),应用Sanger测序对先证者家系成员进行验证,并为先证者姐姐提供产前诊断。本研究通过天津医科大学总医院医学伦理委员会的审查(伦理号：IRB2023-WZ-070)。 结果 先证者现18岁,社会性别为女性,腹腔镜探查未见子宫及卵巢。外周血染色体核型为46,XY, SRY基因检测为阳性,高通量测序显示其携带 AR基因c.1988C>G(p.Ser663Ter)半合子变异。经Sanger测序验证,先证者母亲及姐姐均携带该变异,其父亲与妹妹为野生型。经产前诊断,先证者姐姐第1胎为半合子变异,已终止妊娠;第2胎未携带该变异,顺产一健康男婴。根据美国医学与遗传学学会(ACMG)相关指南,该变异被判定为可能致病性(PM2_Supporting＋PM4＋PP3_Moderate＋PP4)。 结论 AR基因c.1988C>G(p.Ser663Ter)变异可能是先证者CAIS的遗传学病因。对性发育不良患者的准确诊断有赖于医师对临床症状和致病基因的清晰掌握。通过基因检测和遗传咨询,可对家系成员做出准确的诊断、产前诊断及生育指导。     

A novel point mutation of the androgen receptor (F804L) in an Egyptian newborn with complete androgen insensitivity associated with congenital glaucoma and hypertrophic pyloric stenosis

Androgen-insensitivity syndrome (AIS) is a major cause of male pseudohermaphroditism (MPH). Although AIS is usually reported as a monogenic disease resulting from androgen receptor (AR) mutations, on rare occasions it has been observed as part of a multiple congenital anomaly syndrome. We report here a patient who was the first newborn girl of an unrelated couple. Shortly after birth, the diagnoses of congenital glaucoma and pyloric stenosis were made. A detailed history of the father's family revealed that nine members presented glaucoma before 40 years of age. Clinical and ultrasound evaluation showed two inguinal testes, with female external genitalia and no Mullerian derivatives. The patient had a 46,XY karyotype, good testicular response to gonadotrophin stimulation and a remarkably high T : dihydrotestosterone ratio. Sequencing of the five exons of the 5alpha-reductase type 2 gene (SRD5A2) was normal. Conversely, a de novo point mutation was found in exon 6 of the AR gene, resulting in an F804L substitution, which has never been described previously. To our knowledge, the association of complete AIS, congenital glaucoma and pyloric stenosis has also never been reported previously.     

Amber mutation creates a diagnostic MaeI site in the androgen receptor gene of a family with complete androgen insensitivity

We have discovered in the X-linked androgen receptor gene a single nucleotide substitution that is the putative cause of complete androgen insensitivity (resistance) in a family with affected individuals in 2 generations. Earlier studies on the family indicated cosegregation of mutant phenotype and the RFLPs at the loci DXS1 and DXYS1. The mutation is an adenine-to-thymine transversion in exon 8 that changes the sense of codon 882 from lysine to an amber (UAG) translation termination signal. The substitution creates a recognition sequence for the restriction endonuclease MaeI: this permits ready recognition of hemizygotes and heterozygotes after amplification of genomic exon 8 by the polymerase chain reaction. The mutation predicts the synthesis of a truncated receptor that lacks 36 amino acids at the carboxy terminus of its 252-amino acids androgen-binding domain. The cultured genital skin fibroblasts of the one affected patient examined have normal levels of androgen receptor mRNA, but negligible androgen-receptor binding activity. These results accord with a variety of data from spontaneous and artificial mutations indicating that all portions of the steroid binding domain contribute to normal steroid binding by a steroid receptor.     

Novel molecular defects in the androgen receptor gene of Mexican patients with androgen insensitivity

The androgen insensitivity syndrome (AIS) is an X-linked form of male pseudohermaphroditism caused by mutations in the androgen receptor (AR) gene. In the present study, we analyzed the AR gene in 8 patients, 4 sporadic and 2 familial cases with the syndrome, using exon-specific polymerase chain reaction, single-stranded conformational polymorphism and sequencing analysis and identified six new single base mutations, including one nonsense mutation at the hinge region of the receptor. These molecular lesions occurred in the steroid-binding domain (SBD) and all but one affected the first nucleotide of their respective codons. A nonsense mutation in exon 4, which converts a glutamine into a premature termination signal (Q657stop), a missense mutation changing arginine instead of glycine (G743R) and a conservative substitution of leucine with valine at amino acid 830 (L830V) were detected in patients with CAIS. Three other missense mutations located in exons 4 (L701I), 5 (A765S), and 6 (Q802R) were present in individuals bearing a partial form of AIS. These data allow us to reaffirm the view that nonsense mutations in the AR results almost invariably in a CAIS phenotype and underly the importance of the SBD for the AR functional activity.     

Molecular analysis of familial androgen insensitivity syndrome due to replacement of glutamic acid 802 by lysine

We studied a Japanese family presenting at least two cases of complete androgen insensitivity syndrome (CAIS) and negative androgen receptor binding. The index subject showed a 46, XY karyotype and a complete female phenotype. For the purpose of further diagnosis and genetic counseling, molecular analysis of the androgen receptor (AR) gene was performed. Direct sequencing of the AR gene identified a mutation at nucleotide 2935 (A → G). This replacement was a novel missense mutation, resulting in the substitution of glutamic acid 802 by lysine which deleted a recognition site for EcoRI in exon 6 of the AR gene. We identified another affected individual, using chromosome and molecular analysis of the AR gene at exon 6. Furthermore, although heterozygote carriers could not be identified on clinical grounds, molecular identification of healthy individuals and heterozygote carriers in the family members provided definitive information for genetic counseling. We believe that the molecular analysis of familial CAIS is very informative for both the affected individuals and other family members. Received: July 31, 2000 / Accepted: August 31, 2000     

A novel point mutation (R840S) in the androgen receptor in a Brazilian family with partial androgen insensitivity syndrome

Mutations of the androgen receptor gene causing androgen insensitivity syndrome in 46, XY individuals, result in phenotypes ranging from complete female to ambiguous genitalia to males with minor degrees of undervirilization. We studied two Brazilian brothers with partial androgen insensitivity syndrome. They were born with perineal hypospadias, bifid scrotum, small penis and cryptorchidism, and developed gynecomastia at puberty. Genomic DNA was extracted and denaturinggradient gel electrophoresis of exon 7 of the androgen receptor gene followed by sequence analysis revealed a new mutation, a C A transversion, altering codon 840 from arginine (CGT) to serine (AGT). R840 is located in the androgen binding domain, in a “hot spot” region, important for the formation and function of the hormone receptor‐complex and within the region that is involved in androgen receptor dimerization. Replacement of arginine (basic) by serine (neutral and polar) is a nonconservative substitution. Three mutations in this residue (R840C, R840G nonconservative and R840H, conservative) were previously reported in patients with partial androgen insensitivity syndrome and when expressed “in vitro” lead to a subnormal transactivation of a reporter gene. We conclude that the novel R840 mutation in the androgen receptor is the cause of partial androgen insensitivity syndrome in this Brazilian family. Hum Mutat 14:353, 1999. © 1999 Wiley‐Liss, Inc.