Androgen insensitivity syndrome (AIS) is typically characterized by evidence of feminization (i.e., undermasculinization) of the external genitalia at birth, abnormal secondary sexual development in puberty, and infertility in individuals with a 46,XY karyotype. AIS represents a spectrum of defects in androgen action and can be subdivided into three broad phenotypes: Complete androgen insensitivity syndrome (CAIS), with typical female external genitalia. Partial androgen insensitivity syndrome (PAIS) with predominantly female, predominantly male, or ambiguous external genitalia. Mild androgen insensitivity syndrome (MAIS) with typical male external genitalia.

Aarskog-Scott syndrome is a genetic disorder that affects the development of many parts of the body, most commonly the head and face, the hands and feet, and the genitals and urinary system (genitourinary tract). This condition mainly affects males, although females may have mild features of the syndrome.\n\nPeople with Aarskog-Scott syndrome often have distinctive facial features, such as widely spaced eyes (hypertelorism), a small nose, a long area between the nose and mouth (philtrum), and a widow's peak hairline. They frequently have mild to moderate short stature during childhood, but their growth usually catches up with that of their peers during puberty. Hand abnormalities are common in this syndrome and include short fingers (brachydactyly), curved pinky fingers (fifth finger clinodactyly), webbing of the skin between some fingers (cutaneous syndactyly), and a single crease across the palm. Affected individuals can also have wide, flat feet with broad, rounded toes. Other abnormalities in people with Aarskog-Scott syndrome include heart defects and a split in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate).\n\nMost males with Aarskog-Scott syndrome have a shawl scrotum, in which the scrotum surrounds the penis instead of hanging below. Less often, they have undescended testes (cryptorchidism) or a soft out-pouching around the belly-button (umbilical hernia) or in the lower abdomen (inguinal hernia).\n\nThe intellectual development of people with Aarskog-Scott syndrome varies widely. Most individuals with Aarskog-Scott syndrome have normal intelligence; however, some may have mild learning and behavior problems, and in rare cases, severe intellectual disability has been reported.

SRXY11 is characterized by a genital phenotype that may range from predominantly female to predominantly male, including marked sex ambiguity depending on the duration of normal testicular function prior to the loss of testicular tissue. Approximately half of patients present with micropenis and bilateral cryptorchidism, and half present with female-appearing or ambiguous external genitalia (da Silva et al., 2019; McElreavey et al., 2020). The testicular regression syndrome (TRS) was delineated by Sarto and Opitz (1973), who called it the XY gonadal dysgenesis syndrome. It is characterized primarily by the absence of gonads in an XY person. In most cases, uterus and fallopian tubes are absent but small tubular structures interpreted as mullerian or wolffian rudiments (or both) are present. The range of virilizing effects due to early testicular tissue extends from none in phenotypic females with only slightly hypoplastic normal external genitalia, well-formed but hypoplastic uterus, and well-formed tubes (De Marchi et al., 1981) to the anorchic phenotypic male (Edman et al., 1977). Most affected individuals lack a vagina but a urogenital sinus or pseudovaginal urethral outpouching is found. Partial labioscrotal fusion and clitoris enlargement are common, breast development is absent, and postpubertal eunuchoid habitus is the rule. Sometimes nongenital anomalies are present (summary by Rosenberg et al., 1984).

Male patients with hypogonadotropic hypogonadism due to isolated luteinizing hormone (LH) deficiency have normal sexual differentiation but fail to develop spontaneous puberty. Absence of LH alters Leydig cell proliferation and maturation and impairs the onset of normal spermatogenesis, which requires high levels of intratesticular testosterone. Infertility and very low levels of spermatogenesis generally persist in affected men despite long-term exposure to gonadotropin therapy. Female patients exhibit normal pubertal development and menarche, followed by oligomenorrhea and anovulatory secondary amenorrhea (summary by Basciani et al., 2012). Congenital idiopathic hypogonadotropic hypogonadism (IHH) is a disorder characterized by absent or incomplete sexual maturation by the age of 18 years, in conjunction with low levels of circulating gonadotropins and testosterone and no other abnormalities of the hypothalamic-pituitary axis. Idiopathic hypogonadotropic hypogonadism can be caused by an isolated defect in gonadotropin-releasing hormone (GNRH; 152760) release, action, or both. Other associated nonreproductive phenotypes, such as anosmia, cleft palate, and sensorineural hearing loss, occur with variable frequency. In the presence of anosmia, idiopathic hypogonadotropic hypogonadism has been called 'Kallmann syndrome (KS),' whereas in the presence of a normal sense of smell, it has been termed 'normosmic idiopathic hypogonadotropic hypogonadism (nIHH)' (summary by Raivio et al., 2007). Because families have been found to segregate both KS and nIHH, the disorder is here referred to as 'hypogonadotropic hypogonadism with or without anosmia (HH).' For a general phenotypic description and discussion of genetic heterogeneity of hypogonadotropic hypogonadism, see 147950. Reviews Arnhold et al. (2009) noted that the clinical manifestations of female patients with hypogonadotropic hypogonadism due to mutations in LHB are very similar to those of women with hypergonadotropic hypogonadism due to inactivating mutations of the LH receptor (see 238320): all have female external genitalia, spontaneous development of normal pubic hair and breasts at puberty, and normal to late menarche followed by oligoamenorrhea and infertility. Pelvic ultrasound shows a small or normal uterus and normal or enlarged ovaries with cysts. However, women with LHB mutations can be treated with luteinizing hormone or chorionic gonadotropin (CG; 118860) replacement therapy; women with LH receptor mutations are resistant to LH, and no treatment is effective in recovering their fertility.

Premature ovarian failure-2A (POF2A) is a defect of ovarian development and is characterized by primary or secondary amenorrhea, with elevated levels of serum gonadotropins, or by early menopause (Bione et al., 1998). Sala et al. (1997) and Bione et al. (1998) suggested that several genes in a region defined as POF2 (Xq13.3-q22) can influence ovary development and/or oogenesis. For a phenotypic description and a discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Syndrome with the association of hypergonadotropic hypogonadism and cataracts with onset during adolescence. It has been described in three brothers from a consanguineous family. An autosomal recessive mode of transmission appears likely.

Any primary ovarian failure in which the cause of the disease is a mutation in the FIGLA gene.

Nonsyndromic 46,XX testicular disorders/differences of sex development (DSD) are characterized by: the presence of a 46,XX karyotype; external genitalia ranging from typical male to ambiguous; two testicles; azoospermia; absence of müllerian structures; and absence of other syndromic features, such as congenital anomalies outside of the genitourinary system, learning disorders / cognitive impairment, or behavioral issues. Approximately 85% of individuals with nonsyndromic 46,XX testicular DSD present after puberty with normal pubic hair and normal penile size but small testes, gynecomastia, and sterility resulting from azoospermia. Approximately 15% of individuals with nonsyndromic 46,XX testicular DSD present at birth with ambiguous genitalia. Gender role and gender identity are reported as male. If untreated, males with 46,XX testicular DSD experience the consequences of testosterone deficiency.

Sex reversal in an individual with 46,XY karyotype caused by point mutations or deletions in the SRY gene, encoding sex-determining region Y protein.

Nonsyndromic 46,XX testicular disorders/differences of sex development (DSD) are characterized by: the presence of a 46,XX karyotype; external genitalia ranging from typical male to ambiguous; two testicles; azoospermia; absence of müllerian structures; and absence of other syndromic features, such as congenital anomalies outside of the genitourinary system, learning disorders / cognitive impairment, or behavioral issues. Approximately 85% of individuals with nonsyndromic 46,XX testicular DSD present after puberty with normal pubic hair and normal penile size but small testes, gynecomastia, and sterility resulting from azoospermia. Approximately 15% of individuals with nonsyndromic 46,XX testicular DSD present at birth with ambiguous genitalia. Gender role and gender identity are reported as male. If untreated, males with 46,XX testicular DSD experience the consequences of testosterone deficiency.

Any primary ovarian failure in which the cause of the disease is a mutation in the NR5A1 gene.

Myotonic dystrophy type 2 (DM2) is characterized by myotonia and muscle dysfunction (proximal and axial weakness, myalgia, and stiffness), and less commonly by posterior subcapsular cataracts, cardiac conduction defects, insulin-insensitive type 2 diabetes mellitus, and other endocrine abnormalities. While myotonia (involuntary muscle contraction with delayed relaxation) has been reported during the first decade, onset is typically in the third to fourth decade, most commonly with fluctuating or episodic muscle pain that can be debilitating and proximal and axial weakness of the neck flexors and the hip flexors. Subsequently, weakness occurs in the elbow extensors and finger flexors. Facial weakness and weakness of the ankle dorsiflexors are less common. Myotonia rarely causes severe symptoms. In a subset of individuals, calf hypertrophy in combination with brisk reflexes is notable.

This multisystem disorder is characterized by moyamoya disease, short stature, hypergonadotropic hypogonadism, and facial dysmorphism. Other variable features include dilated cardiomyopathy, premature graying of the hair, and early-onset cataracts. Moyamoya disease is a progressive cerebrovascular disorder characterized by stenosis or occlusion of the internal carotid arteries and the main branches, leading to the development of small collateral vessels (moyamoya vessels) at the base of the brain. Affected individuals can develop acute neurologic events due to stroke-like episodes (summary by Miskinyte et al., 2011). For a general phenotypic description and a discussion of genetic heterogeneity of moyamoya disease, see MYMY1 (252350).

Any 46 XX gonadal dysgenesis in which the cause of the disease is a mutation in the PSMC3IP gene.

Early activation of the hypothalamic-pituitary-gonadal axis results in gonadotropin-dependent precocious puberty, also known as central precocious puberty, which is clinically defined by the development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. Pubertal timing is influenced by complex interactions among genetic, nutritional, environmental, and socioeconomic factors. The timing of puberty is associated with risks of subsequent disease: earlier age of menarche in girls is associated with increased risk of breast cancer, endometrial cancer, obesity, type 2 diabetes, and cardiovascular disease. Central precocious puberty has also been associated with an increased incidence of conduct and behavior disorders during adolescence (summary by Abreu et al., 2013). Genetic Heterogeneity of Central Precocious Puberty Central precocious puberty-2 (CPPB2; 615346) is caused by mutation in the MKRN3 gene (603856) on chromosome 15q11.

Perrault syndrome is characterized by sensorineural hearing loss (SNHL) in males and females and ovarian dysfunction in females. SNHL is bilateral and ranges from profound with prelingual (congenital) onset to moderate with early-childhood onset. When onset is in early childhood, hearing loss can be progressive. Ovarian dysfunction ranges from gonadal dysgenesis (absent or streak gonads) manifesting as primary amenorrhea to primary ovarian insufficiency (POI) defined as cessation of menses before age 40 years. Fertility in affected males is reported as normal (although the number of reported males is limited). Neurologic features described in some individuals with Perrault syndrome include learning difficulties and developmental delay, cerebellar ataxia, and motor and sensory peripheral neuropathy.

Premature ovarian failure (POF), the endpoint of primary ovarian insufficiency, affects approximately 1% of women worldwide. Patients with POF present with at least a 6-month history of amenorrhea and elevated plasma levels of follicle-stimulating hormone (more than 40 mIU per milliliter). The disorder can result from premature depletion of the follicle pool, follicular atresia, follicle growth arrest, or ovarian dysgenesis (see 233300). In approximately 10 to 15% of patients with POF, a genetic cause has been determined (summary by Caburet et al., 2014). For general phenotypic information and a discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Nonsyndromic primary ovarian insufficiency, which is characterized by amenorrhea with elevated gonadotropin levels, is observed in 1% of otherwise healthy women under the age of 40 years (summary by Wang et al., 2014). For a general phenotypic description and discussion of the genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Any azoospermia in which the cause of the disease is a mutation in the TAF4B gene.

Any azoospermia in which the cause of the disease is a mutation in the ZMYND15 gene.

A rare genetic disorder of sex development characterized by primary amenorrhea, short stature, delayed bone age, decreased levels of estradiol, elevated levels of follicle-stimulating hormone and luteinizing hormone, absent or underdeveloped uterus and ovaries, delayed development of pubic and axillary hair and normal 46,XX karyotype.

Premature ovarian failure-10 (POF10) represents a syndrome characterized by primary amenorrhea, hypergonadotropic ovarian insufficiency, and genomic instability in somatic cells. For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360). For a discussion of genetic heterogeneity of age at natural menopause, see MENOQ1 (300488).

Any Seckel syndrome in which the cause of the disease is a mutation in the NSMCE2 gene.

Premature ovarian failure-11 (POF11) is characterized by secondary amenorrhea and hypergonadotropic ovarian insufficiency, with elevated serum follicle-stimulating hormone (FSH; see 136530) levels before age 40 years (Qin et al., 2015). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Premature ovarian failure-13 (POF13) is characterized by female infertility due to secondary amenorrhea in the third decade of life. Patients exhibit atrophic ovaries devoid of follicles (Guo et al., 2017). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Premature ovarian failure-14 (POF14) is characterized by amenorrhea, hypoestrogenism, and elevated gonadotropin levels (Franca et al., 2018). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Spermatogenic failure-28 (SPGF28) is characterized by nonobstructive azoospermia, with a Sertoli cell-only phenotype observed in testicular tissue (Kasak et al., 2018). For a discussion of genetic heterogeneity of spermatogenic failure, see SPGF1 (258150).

Premature ovarian failure-15 (POF15) is characterized by primary amenorrhea, oligomenorrhea, or secondary amenorrhea; small ovaries with reduced or absent follicles; and elevated gonadotropic hormones (Fouquet et al., 2017; Jaillard et al., 2020; Heddar et al., 2022). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Ovarian dysgenesis-7 (ODG7) is characterized by primary amenorrhea, delayed puberty, elevated gonadotropic hormones, and small uterus and ovaries. Ovarian histology shows fibrotic ovaries without follicles (Chen et al., 2018). For a discussion of genetic heterogeneity of ovarian dysgenesis, see ODG1 (233300).

Ovarian dysgenesis-8 (ODG8) is characterized by complete lack of estrogen action, resulting in absent breast development, primary amenorrhea, and osteoporosis (Lang-Muritano et al., 2018). For a discussion of genetic heterogeneity of ovarian dysgenesis, see ODG1 (233300).

Myoectodermal gonadal dysgenesis syndrome (MEGD) is characterized by 46,XY complete or partial gonadal dysgenesis, or 46,XX gonadal dysgenesis, in association with extragonadal anomalies, including low birth weight, typical facies, rod and cone dystrophy, sensorineural hearing loss, omphalocele, anal atresia, renal agenesis, skeletal abnormalities, dry and scaly skin, severe myopathy, and neuromotor delay. Dysmorphic facial features along with muscular habitus are the hallmarks of the syndrome. Abnormal hair patterning with frontal upsweep and additional whorls, eyebrow abnormalities comprising broad, arched, and sparse or thick eyebrows, underdeveloped alae nasi, smooth philtrum, and low-set ears with overfolded helices facilitate a gestalt diagnosis. (Guran et al., 2019; Altunoglu et al., 2022).

Premature ovarian failure-16 (POF16) is characterized by onset of amenorrhea early in the fourth decade of life, accompanied by elevated follicle-stimulating hormone (FSH; see 136530) levels and low estradiol levels. Ovaries are smaller than normal and show a solid echo pattern with no antral follicle (Zhang et al., 2018).

Premature ovarian failure-17 (POF17) is characterized by early cessation of menses after initial menarche, with small ovaries and uterus (Zhang et al., 2019). For a discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Premature ovarian failure-18 (POF18) is characterized by irregular menstrual cycles and cessation of menstruation in the third decade of life. The uterus is small; ovaries may be small or rudimentary, and do not show follicular activity (Fan et al., 2021). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Ovarian dysgenesis-9 (ODG9) is characterized by severe nonsyndromic primary ovarian insufficiency with primary amenorrhea, hypoplastic or absent ovaries, and delayed bone age. Patient cells show evidence of chromosomal instability (Smirin-Yosef et al., 2017; Heddar et al., 2022). For a general phenotypic description and discussion of genetic heterogeneity of ovarian dysgenesis, see ODG1 (233300).

X-linked spermatogenic failure-4 (SPGFX4) is characterized by male infertility due to azoospermia or oligoasthenoteratozoospermia. Some patients show maturation arrest, and Sertoli cell-only phenotype has been observed (Hardy et al., 2021; Arafat et al., 2021; Kherraf et al., 2022). For a discussion of genetic heterogeneity of spermatogenic failure, see SPGF1 (258150).

Ovarian dysgenesis-10 (ODG10) is characterized by primary amenorrhea and absent puberty. The uterus is small and prepubertal, and ovaries are streak or not visualized on ultrasound (McGlacken-Byrne et al., 2022). Mutation in the ZSWIM7 gene also causes male infertility due to spermatogenic failure (SPGF71; 619831). For a general phenotypic description and discussion of genetic heterogeneity of ovarian dysgenesis, see ODG1 (233300).

Premature ovarian failure-20 (POF20) is characterized by female infertility due to secondary amenorrhea. Some patients exhibit atrophic ovaries lacking follicles (Carlosama et al., 2017; Akbari et al., 2021; Wyrwoll et al., 2022). For a general phenotypic description and a discussion of genetic heterogeneity of POF, see POF1 (311360).

Spermatogenic failure-75 (SPGF75) is characterized by male infertility due to nonobstructive azoospermia resulting from maturation arrest at the spermatocyte stage (Krausz et al., 2020; Yao et al., 2021). For a general phenotypic description and discussion of genetic heterogeneity of spermatogenic failure, see SPGF1 (258150).

Spermatogenic failure-77 (SPGF77) is characterized by male infertility due to extreme oligozoospermia or azoospermia. Nearly all spermatozoa present on semen analysis are morphologically abnormal, with amorphous, enlarged, and/or fragmented heads, and some are multiflagellated. Testicular tissue shows arrest at the round spermatid stage (Wyrwoll et al., 2022). For a general phenotypic description and a discussion of genetic heterogeneity of spermatogenic failure, see SPGF1 (258150).

Premature ovarian failure-21 (POF21) is characterized by female infertility due to primary or secondary amenorrhea. Ovaries are small, atrophic, or nonvisualized on ultrasound (Tucker et al., 2019; Tucker et al., 2022). For a general phenotypic description and a discussion of genetic heterogeneity of POF, see POF1 (311360).

Ziegler-Huang syndrome (ZHS) is a bone marrow failure syndrome characterized by severe growth retardation responsive to growth hormone (GH1; 139250) treatment, testicular hypoplasia, and progressive bone marrow failure, with thrombocytopenia and macrocytosis developing in childhood (Huang et al., 2023). For a general phenotypic description and discussion of genetic heterogeneity of bone marrow failure syndromes, see BMFS1 (614675).

Premature ovarian failure-22 (POF22) is characterized by female infertility, with small to atrophic ovaries and no visible ovarian follicles (Wu et al., 2022; Zhang et al., 2022). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).

Premature ovarian failure-23 (POF23) is characterized by female infertility due to reduction of ovarian reserve. After normal menarche, patients experience oligomenorrhea and secondary amenorrhea (Caburet et al., 2019). For a general phenotypic description and discussion of genetic heterogeneity of premature ovarian failure, see POF1 (311360).