Androgen insensitivity syndrome （AIS）, an X-linked recessive genetic disorder of sex development, is caused by mutations in the androgen receptor （AR） gene, and is characterized by partial or complete inability of...Androgen insensitivity syndrome （AIS）, an X-linked recessive genetic disorder of sex development, is caused by mutations in the androgen receptor （AR） gene, and is characterized by partial or complete inability of specific tissues to respond to androgens in individuals with the 46,XY karyotype. This study aimed to investigate AR gene mutations and to characterize genotype-phenotype correlations. Ten patients from unrelated families, aged 2-31 years, were recruited in the study. Based on karyotype, altered hormone profile, and clinical manifestations, nine patients were preliminarily diagnosed with complete AIS and one with partial AIS. Genetic analysis of AR gene revealed the existence of 10 different mutations, of which five were novel （c.2112 C〉G[p.STO4R], c.2290T〉A[p.Y764N], c.2626C〉T[p.Q876X], c.933dupC[p.K313Qfs＊28], and c.1067delC[p.A356Efs＊123]）; the other five were previously reported （c.1789G〉A[p.A597T], c.2566C〉T[p.R856C], c.2668G〉A[p.V890M], c.2679C〉T[p.P893L], and c.1605C〉G[p.Y535X]）. Regarding the distribution of these mutations, 60.0% were clustered in the ligand-binding domain of AR gene. Exons 1 and 8 of AR gene each accounted for 30.0% （3/10） of all mutations. Most of the truncation mutations were in exon 1 and missense mutations were mainly located in exons 4-8. Our study expands the spectrum of AR gene mutations and confirms the usefulness of AR gene sequencing to support a diagnosis of AIS and to enable prenatal or antenatal screening.展开更多
Mutations in the X-linked androgen receptor （AR） gene cause androgen insensitivity syndrome （AIS）, resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity （CAI...Mutations in the X-linked androgen receptor （AR） gene cause androgen insensitivity syndrome （AIS）, resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity （CAIS） produces a female external phenotype, whereas cases with partial androgen insensitivity （PALS） have various ambiguities of the genitalia. Mild androgen insensitivity （MAIS） is characterized by undermasculinization and gynecomastia. Here we describe a 2-month-old 46,XY female patient, with all of the characteristics of CAIS. Defects in testosterone （T） and dihydrotestosterone （DHT） synthesis were excluded. Sequencing of the AR gene showed the presence in exon 6 of a T to C transition in the second base of codon 790, nucleotide position 2369, causing a novel missense Leu790Pro mutation in the ligand-binding domain of the AR protein. The identification of a novel AR mutation in a girl with CAIS provides significant information due to the importance of missense mutations in the ligand-binding domain of the AR, which are able to induce functional abnormalities in the androgen binding capability, stabilization of active conformation, or interaction with coactivators.展开更多
基金The authors are grateful to the patients and their family members for participating in this study. This study was supported by grants from the National Natural Science Foundation of China （81771645 and 81471432 to YQT）.
文摘Androgen insensitivity syndrome （AIS）, an X-linked recessive genetic disorder of sex development, is caused by mutations in the androgen receptor （AR） gene, and is characterized by partial or complete inability of specific tissues to respond to androgens in individuals with the 46,XY karyotype. This study aimed to investigate AR gene mutations and to characterize genotype-phenotype correlations. Ten patients from unrelated families, aged 2-31 years, were recruited in the study. Based on karyotype, altered hormone profile, and clinical manifestations, nine patients were preliminarily diagnosed with complete AIS and one with partial AIS. Genetic analysis of AR gene revealed the existence of 10 different mutations, of which five were novel （c.2112 C〉G[p.STO4R], c.2290T〉A[p.Y764N], c.2626C〉T[p.Q876X], c.933dupC[p.K313Qfs＊28], and c.1067delC[p.A356Efs＊123]）; the other five were previously reported （c.1789G〉A[p.A597T], c.2566C〉T[p.R856C], c.2668G〉A[p.V890M], c.2679C〉T[p.P893L], and c.1605C〉G[p.Y535X]）. Regarding the distribution of these mutations, 60.0% were clustered in the ligand-binding domain of AR gene. Exons 1 and 8 of AR gene each accounted for 30.0% （3/10） of all mutations. Most of the truncation mutations were in exon 1 and missense mutations were mainly located in exons 4-8. Our study expands the spectrum of AR gene mutations and confirms the usefulness of AR gene sequencing to support a diagnosis of AIS and to enable prenatal or antenatal screening.
文摘Mutations in the X-linked androgen receptor （AR） gene cause androgen insensitivity syndrome （AIS）, resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity （CAIS） produces a female external phenotype, whereas cases with partial androgen insensitivity （PALS） have various ambiguities of the genitalia. Mild androgen insensitivity （MAIS） is characterized by undermasculinization and gynecomastia. Here we describe a 2-month-old 46,XY female patient, with all of the characteristics of CAIS. Defects in testosterone （T） and dihydrotestosterone （DHT） synthesis were excluded. Sequencing of the AR gene showed the presence in exon 6 of a T to C transition in the second base of codon 790, nucleotide position 2369, causing a novel missense Leu790Pro mutation in the ligand-binding domain of the AR protein. The identification of a novel AR mutation in a girl with CAIS provides significant information due to the importance of missense mutations in the ligand-binding domain of the AR, which are able to induce functional abnormalities in the androgen binding capability, stabilization of active conformation, or interaction with coactivators.
