Clinical, hormonal and genetic characteristics of androgen insensitivity syndrome in 39 Chinese patients

Analysis of genetic and clinical characteristics of androgen insensitivity syndrome: a cohort study including 12 families

CONTEXT

Androgen insensitivity syndrome (AIS) manifests itself as variable symptoms of under-virilization in patients with 46,XY disorders caused by androgen receptor (AR) gene variants. This large-sample study aimed to correlate the genotypes and phenotypes to the fertility of individuals.

METHODS

This was a cohort study that analyzed the genetic and clinical characteristics of patients with AIS from a single center in China.

RESULTS

The 117 patients were divided into 53 with complete AIS (CAIS) and 64 with partial AIS (PAIS). At their first visit, the median age was 1.83 years (0.92-4.17), and the external masculinization score was 3.0 (2.0-6.0). At the last follow-up, 92% (49/53) of patients with CAIS maintained their female gender, and 94% (60/64) of patients with PAIS were raised as males. No gender anxiety was observed in this study. Eighty-eight AR variants were identified, with 31 (35%) being unreported. Moreover, 24% (21/88) occurred more than once. The variants that appeared most frequently were located at amino acid 841, including p.R841H (n = 5) and p.R841C (n = 2). Variants p.N706S, p.R856H, and p.A871V were each observed 4 times. In terms of inheritance, 83% of patients with parental verification inherited variants from their mothers. We also observed that the variants from 1 case were inherited from his maternal grandfather who had hypospadias.

CONCLUSION

Most children with PAIS were raised as males. The abundance of maternally inheritable variants and the presence of case of preserved fertility indicate the fertility potential in patients with AIS. Hence, we recommend a careful evaluation of gonadectomy when fertility preservation is being considered.

Sex assignment and psychosexual peculiarities of individuals with different forms of androgen insensitivity syndrome: A qualitative study

Background

A mismatch between chromosomal, gonadal, and phenotypic sexes in individuals with androgen insensitivity syndrome (AIS) creates problems in sex assignment and psychosexual identification.

Objective

To identify psychosexual and sex assignment peculiarities of individuals with different forms of AIS.

Materials and Methods

In this qualitative study, 41 individuals with AIS aged between 15 and 31 yr who referred to the Universe Center for Reproductive Medicine Tbilisi, Georgia between 2016 and 2021 were studied. All individuals underwent clinical, genealogical, hormonal, ultrasonographic, and cytogenetic examinations. In-depth interviews and medical records assessed psychosexual profiles and sex assignment histories.

Results

32 cases were diagnosed with the complete form of AIS (CAIS), 8 individuals with the partial form (PAIS), and one with a mild form (MAIS). Individuals with CAIS and PAIS were assessed at birth and raised as girls. Individuals with CAIS and female psychosexual disposition were referred to us due to amenorrhea. Adolescent individuals with PAIS assessed as girls referred to us due to masculinization detected in puberty. An individual with MAIS was assessed at birth and raised as a boy with male genitalia. All individuals with AIS had typical hormonal data and sex chromosome complex for men. 20 sexually active individuals with CAIS had penile-vaginal contact with the man. None of the individuals with CAIS and PAIS thought about gender reassignment after being diagnosed, only the individual with MAIS aimed for male-to-female transition.

Conclusion

Psychosexual identification remains a significant challenge in AIS management. Detection of female psychosexual disposition in one participant that is unusual to MAIS may be associated with somatic mosaicism of the androgen receptor gene.

Phenotype and genetic characteristics in 20 Chinese patients with 46,XY disorders of sex development

PURPOSE

46,XY disorders of sex development (DSD) is the most complicated and common type of DSD. To date, more than 30 genes have been identified associated with 46,XY DSD. However, the mutation spectrum of 46,XY DSD is incomplete owing to the high genetic and clinical heterogeneity. This study aims to provide clinical and mutational characteristics of 18 Chinese patients with 46,XY DSD.

METHODS

A total of 20 unrelated individuals with 46,XY DSD were recruited. Whole-exome sequencing (WES) or custom-panel sequencing combined Sanger sequencing were performed to detect the pathogenic mutations. The pathogenicity of the variant was assessed according to the American College of Medical Genetics and Genomics (ACMG) guidance and technical standards recommended by the ACMG and the Clinical Genome Resource (ClinGen).

RESULTS

Six patients harbored NR5A1 mutations; two patients harbored NR0B1 mutations; six patients harbored SRD5A2 mutations; six patients harbored AR mutations. Six novel genetic variants were identified involved in three genes (NR5A1, NR0B1, and AR).

CONCLUSION

We determined the genetic etiology for all enrolled patients. Our study expanded the mutation spectrum of 46,XY DSD and provided diagnostic evidence for patients with the same mutation in the future.

Clinical characteristics, AR gene variants, and functional domains in 64 patients with androgen insensitivity syndrome

BACKGROUND

Androgen insensitivity syndrome (AIS) is caused by abnormal androgen receptor (AR) genes that show variable genotypes and phenotypes. However, the correlation between genotype and phenotype is unclear.

METHODS

We retrospectively evaluated 64 patients with AIS at Shanghai Children's Hospital from 2015 to 2022. We analysed the clinical data of the patients, including hormone levels, AR gene variants, and functional domains.

RESULTS

Variants occurred in the 3 major functional domains in 56 patients, including 23 patients with complete androgen insensitivity syndrome (CAIS) and 33 with partial androgen insensitivity syndrome (PAIS). The incidence of nonscrotal fusion (P = 0.019) and proximal urethral opening (P = 0.0002) in the ligand-binding domain (LBD) group was higher than that in the non-LBD group. The phallus length in the LBD group was significantly shorter than that in the non-LBD group (P = 0.009). The external masculinization score (EMS) in the LBD group was significantly lower than that in the non-LBD group (P = 0.013). The levels of inhibin-B (INHB; P = 0.0007), basal luteinizing hormone (LH; P = 0.033), LH peak (P = 0.002), and testosterone (T) after human chorionic gonadotropin (HCG) stimulation (P = 0.001) in the LBD group were higher than those in the non-LBD group. There were 53 variants in 64 patients, including 42 reported and 11 novel AR variants, including p.Met247Arg, p.Asp266Glyfs*39, p.Arg362Serfs*140, p.Ala385Val, p.Glu541Asp, p.Pro613Leu, p.Pro695Leu, p.Asn757Asp, c.1616 + 1dup, c.1886-1G > A and exon 5-7 deletion.

CONCLUSIONS

The EMS of patients with AIS in the LBD group was significantly lower than that in the non-LBD group. The phallus length was shorter, and the incidences of proximal urethral opening and nonscrotal fusion were higher, suggesting that the phenotypes in the LBD group were more severe. The levels of INHB, basal LH, peak LH, and T after HCG stimulation in the LBD group were higher than those in the non-LBD group, suggesting that androgen resistance in the LBD group was more severe. We identified 53 variants in 64 patients: 42 reported and 11 novel AR variants. These findings provide new and deeper insight into AIS diagnosis and genetic assessment of AIS.

Identification of the Rare Ala871Glu Mutation in the Androgen Receptor Gene Leading to Complete Androgen Insensitivity Syndrome in an Adolescent Girl with Primary Amenorrhea

Complete Androgen Insensitivity Syndrome (CAIS) is a rare genetic condition by mutations in the androgen receptor (AR) gene resulting in target issue resistance to androgens and a female phenotype in genetically male individuals. A 16-year-old phenotypically female individual presented to our clinic with primary amenorrhea. Her clinical evaluation showed normal female external genitalia, Tanner III breast development and sparse pubic and axillary hair (Tanner stage II). Hormonal assessment revealed increased concentrations of Luteinizing Hormone (LH), Testosterone and Antimüllerian Hormone (AMH). Image studies detected no uterus or gonads, but a blind vagina and the karyotype was 46, XY. These findings suggested the diagnosis of CAIS, and genetic testing of the AR gene revealed a rare pathogenic mutation of cytosine to adenine (c.2612C>A) replacing alanine with glutamic acid at position 871 (p.Ala871Glu) in the AR, previously described once in two adult sisters. The patient underwent gonadectomy and received hormonal replacement therapy. This study expands the AR mutation database and shows the complexity and the importance of prompt diagnosis, proper management, and follow-up for CAIS patients, underlining the need for standardized protocols.

Challenges in the Diagnosis of XY Differences of Sexual Development

Background: We report the clinical case of female patient with 46,XY difference of sexual development (DSD) and discuss the challenges in the differential diagnosis between complete gonadal dysgenesis (also called Swyer syndrome) and complete androgen insensitivity syndrome. Case Presentation: The patient's with primary amenorrhea gynaecological examination and magnetic resonance imaging (MRI) revealed the absence of the uterus and a very short vagina. Two sclerotic structures, similar to ovaries, were recognised bilaterally in the iliac regions. Hormonal assay tests revealed hypergonadotropic hypogonadism and the testosterone level was above normal. The karyotype was 46,XY and a diagnosis of Swyer syndrome was made. At the age of 41, the patient underwent a gynaecological review and after evaluating her tests and medical history, the previous diagnosis was questioned. Therefore, a molecular analysis of sex-determining region Y (SRY) and androgen receptor (AR) genes was made and the results instead led to a definite diagnosis of complete androgen insensitivity syndrome. Conclusions: The presented case illustrates that differentiating between complete gonadal dysgenesis and complete androgen insensitivity can be challenging. A well-established diagnosis is crucial because the risk of malignancy is different in those two syndromes, as well as the timing and importance of gonadectomy.

Testicular Sertoli Cell Hormones in Differences in Sex Development

The Sertoli cells of the testes play an essential role during gonadal development, in addition to supporting subsequent germ cell survival and spermatogenesis. Anti-Müllerian hormone (AMH) is a member of the TGF-β superfamily, which is secreted by immature Sertoli cells from the 8th week of fetal gestation. lnhibin B is a glycoprotein, which is produced by the Sertoli cells from early in fetal development. In people with a Difference or Disorder of Sex Development (DSD), these hormones may be useful to determine the presence of testicular tissue and potential for spermatogenesis. However, fetal Sertoli cell development and function is often dysregulated in DSD conditions and altered production of Sertoli cell hormones may be detected throughout the life course in these individuals. As such this review will consider the role of AMH and inhibin B in individuals with DSD.

AMH Regulation by Steroids in the Mammalian Testis: Underlying Mechanisms and Clinical Implications

Anti-Müllerian hormone (AMH) is a distinctive biomarker of the immature Sertoli cell. AMH expression, triggered by specific transcription factors upon fetal Sertoli cells differentiation independently of gonadotropins or sex steroids, drives Müllerian duct regression in the male, preventing the development of the uterus and Fallopian tubes. AMH continues to be highly expressed by Sertoli until the onset of puberty, when it is downregulated to low adult levels. FSH increases testicular AMH output by promoting immature Sertoli cell proliferation and individual cell expression. AMH secretion also showcases a differential regulation exerted by intratesticular levels of androgens and estrogens. In the fetus and the newborn, Sertoli cells do not express the androgen receptor, and the high androgen concentrations do not affect AMH expression. Conversely, estrogens can stimulate AMH production because estrogen receptors are present in Sertoli cells and aromatase is stimulated by FSH. During childhood, sex steroids levels are very low and do not play a physiological role on AMH production. However, hyperestrogenic states upregulate AMH expression. During puberty, testosterone inhibition of AMH expression overrides stimulation by estrogens and FSH. The direct effects of sex steroids on AMH transcription are mediated by androgen receptor and estrogen receptor α action on AMH promoter sequences. A modest estrogen action is also mediated by the membrane G-coupled estrogen receptor GPER. The understanding of these complex regulatory mechanisms helps in the interpretation of serum AMH levels found in physiological or pathological conditions, which underscores the importance of serum AMH as a biomarker of intratesticular steroid concentrations.

Up-to-Date Clinical and Biochemical Workup of the Child and the Adolescent with a Suspected Disorder of Sex Development

BACKGROUND

The suspicion of a disorder of sex development (DSD) often arises at birth, when the newborn presents with ambiguous genitalia, or even during prenatal ultrasound assessments. Less frequently, the aspect of the external genitalia is typically female or male, and the diagnosis of DSD may be delayed until a karyotype is performed for another health issue, or until pubertal age when a girl presents with absence of thelarche and/or menarche or a boy consults for gynaecomastia and/or small testes.

SUMMARY

In this review, we provide a practical, updated approach to clinical and hormonal laboratory workup of the newborn, the child, and the adolescent with a suspected DSD. We focus on how to specifically address the diagnostic approach according to the age and presentation. Key Message: We particularly highlight the importance of a detailed anatomic description of the external and internal genitalia, adequate imaging studies or surgical exploration, the assessment of reproductive hormone levels - especially testosterone, anti-Müllerian hormone, 17-hydroxyprogesterone, and gonadotropins - and karyotyping.

Hormone resistance in children: what primary care physicians need to know

Hormone resistance is defined as a reduced or absence of target tissues responsiveness to a hormone, where the presentation is related to either a relative lack or excess of hormones. Various disorders of hormone resistance were encountered including, Laron syndrome, nephrogenic diabetes insipidus, thyroid hormone resistance syndrome, pseudohypoparathyroidism, insulin resistance, familial glucocorticoid deficiency, pseudohypoaldosteronism, X linked hypophosphatemic rickets and androgen insensitivity syndrome. The article gives a summary that presents, in concentrated form, what the primary care physicians need to know about recognition, clinical presentation, diagnosis, and management of various hormone resistance in children.

Late Diagnosis of Partial Androgen Insensitivity Syndrome in a Peruvian Child

Disorders of sexual differentiation are congenital pathologies characterized by atypical development of genetic, gonadal, or phenotypic sex. These are caused by the alteration of any primordial phases of sexual development and may be evident at birth or in the later stage of life. Here, we present the case of a nine-year-old Peruvian school patient who has female gender assigned at birth, has no contributory antecedents and was found to have clitoromegaly and hypospadia on physical examination. In the blood tests, anti-Müllerian hormone and testosterone were found, and 46 XY karyotype and sex-determining region Y (SRY) genes were present. On abdominal ultrasound, testicles were found in the inguinal canals. The human chorionic gonadotropin (HCG) stimulation test was conducted, which allowed us to rule out defects in testosterone biosynthesis and enzyme defects in dihydrotestosterone production; the main suspected diagnosis was partial androgen insensitivity syndrome (PAIS). A multidisciplinary medical meeting was held, accepting the patient’s desire to opt for the male gender, after acceptance by the parents. Thus, the patient underwent bilateral orchidopexy and genitoplasty. He is currently receiving therapy with testosterone, with an adequate response to the treatment and the molecular study confirmed the androgen-receptor gene mutation. In conclusion, we highlight the importance of a timely multidisciplinary diagnosis and management of disorders of sexual differentiation to avoid premature gender assignment and major social and family repercussions that it implies.

The challenges of androgen insensitivity syndrome

Androgen insensitivity syndrome (AIS) is an X-linked recessive genetic syndrome that occurs as result of an androgen receptor mutation; it affects the normal masculinization process in chromosomal male patients. More than 900 androgen receptor mutations that can lead to AIS have been identified. The complete androgen insensitivity is characterized by a total lack of response to androgens, usually in patients with 46XY karyotype but with feminine phenotype. Primary amenorrhoea and inguinal swellings in female patients are the main signs that could raise suspicion for this syndrome. Patients with partial androgen insensitivity have ambiguous genitalia at birth and gynecomastia during puberty, whereas those with mild androgen insensitivity present a normal male phenotype but altered spermatogenesis during adulthood and pubertal gynecomastia. The diagnosis of AIS often proves to be a challenge; its management is complex and requires a multidisciplinary approach to meet decision-making challenges in sex assignment, fertility and timing of gonadectomy, psychological outcomes and genetic counselling.

Disorders of Sex Development: Classification, Review, and Impact on Fertility

In this review, the elements included in both sex determination and sex differentiation are briefly analyzed, exposing the pathophysiological and clinical classification of disorders or anomalies of sex development. Anomalies in sex determination without sex ambiguity include gonadal dysgenesis, polysomies, male XX, and Klinefelter syndrome (dysgenesis and polysomies with a female phenotype; and sex reversal and Klinefelter with a male phenotype). Other infertility situations could also be included here as minor degrees of dysgenesis. Anomalies in sex determination with sex ambiguity should (usually) include testicular dysgenesis and ovotesticular disorders. Among the anomalies in sex differentiation, we include: (1) males with androgen deficiency (MAD) that correspond to those individuals whose karyotype and gonads are male (XY and testes), but the phenotype can be female due to different hormonal abnormalities. (2) females with androgen excess (FAE); these patients have ovaries and a 46,XX karyotype, but present varying degrees of external genital virilization as a result of an enzyme abnormality that affects adrenal steroid biosynthesis and leads to congenital adrenal hyperplasia; less frequently, this can be caused by iatrogenia or tumors. (3) Kallman syndrome. All of these anomalies are reviewed and analyzed herein, as well as related fertility problems.