Polycystic ovary syndrome is a condition that affects women in their child-bearing years and alters the levels of multiple hormones, resulting in problems affecting many body systems.\n\nMost women with polycystic ovary syndrome produce excess male sex hormones (androgens), a condition called hyperandrogenism. Having too much of these hormones typically leads to excessive body hair growth (hirsutism), acne, and male pattern baldness.\n\nHyperandrogenism and abnormal levels of other sex hormones prevent normal release of egg cells from the ovaries (ovulation) and regular menstrual periods, leading to difficulty conceiving a child (subfertility) or a complete inability to conceive (infertility). For those who achieve pregnancy, there is an increased risk of complications and pregnancy loss. Due to irregular and infrequent menstruation and hormone abnormalities, affected women have an increased risk of cancer of the uterine lining (endometrial cancer).\n\nIn polycystic ovary syndrome, one or both ovaries can contain multiple small, immature ovarian follicles that can appear as cysts on medical imaging. Normally, ovarian follicles contain egg cells, which are released during ovulation. In polycystic ovary syndrome, abnormal hormone levels prevent follicles from growing and maturing to release egg cells. Instead, these immature follicles accumulate in the ovaries. Affected women can have 12 or more of these follicles. The number of these follicles usually decreases with age.\n\nAbout half of all women with polycystic ovary syndrome are overweight or have obesity and are at increased risk of a fatty liver. Additionally, many women with polycystic ovary syndrome have elevated levels of insulin, which is a hormone that helps control levels of blood glucose, also called blood sugar. By age 40, about 10 percent of overweight women with polycystic ovary syndrome develop abnormally high blood glucose levels (type 2 diabetes), and up to 35 percent develop prediabetes (higher-than-normal blood glucose levels that do not reach the cutoff for diabetes). Obesity and increased insulin levels (hyperinsulinemia) further increase the production of androgens in polycystic ovary syndrome.\n\nWomen with polycystic ovary syndrome are also at increased risk for developing metabolic syndrome, which is a group of conditions that include high blood pressure (hypertension), increased belly fat, high levels of unhealthy fats and low levels of healthy fats in the blood, and high blood glucose levels. About 20 percent of affected adults experience pauses in breathing during sleep (sleep apnea). Women with polycystic ovary syndrome are more likely than women in the general popluation to have mood disorders such as depression.

Prader-Willi syndrome (PWS) is characterized by severe hypotonia and feeding difficulties in early infancy, followed in later infancy or early childhood by excessive eating and gradual development of morbid obesity (unless eating is externally controlled). Motor milestones and language development are delayed. All individuals have some degree of cognitive impairment. A distinctive behavioral phenotype (with temper tantrums, stubbornness, manipulative behavior, and obsessive-compulsive characteristics) is common. Hypogonadism is present in both males and females and manifests as genital hypoplasia, incomplete pubertal development, and, in most, infertility. Short stature is common (if not treated with growth hormone); characteristic facial features, strabismus, and scoliosis are often present.

Adrenocorticotropic hormone (ACTH) hypersecretion by corticotroph adenomas of the pituitary result in excess cortisol secretion, or Cushing disease. The clinical features of Cushing disease include central obesity, moon facies, 'buffalo hump,' diabetes, hypertension, fatigue, easy bruising, depression, and reproductive disorders. Cushing disease is associated with increased morbidity and mortality, mainly due to cardiovascular or cerebrovascular disease and infections (summary by Perez-Rivas et al., 2015). Mutations in the USP8 gene, leading to an upregulated epidermal growth factor receptor (EGFR; 131550) pathway, have been identified in about 36 to 62% of corticotroph adenomas (summary by Mete and Lopes, 2017).

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.

A rare familial partial lipodystrophy with characteristics of adult onset of distal lipoatrophy with gluteofemoral fat loss, as well as increased fat accumulation in the face and trunk and visceral adiposity. Additional manifestations include diabetes mellitus, atherogenic dyslipidemia, eyelid xanthelasma, arterial hypertension, cardiovascular disease, hepatic steatosis, acanthosis nigricans on axilla and neck, hirsutism, and muscular hypertrophy of the lower limbs. Caused by heterozygous mutation in the PPARG gene on chromosome 3p25.

Wolfram syndrome-2 (WFS2) is an autosomal recessive neurodegenerative disorder characterized by diabetes mellitus, high frequency sensorineural hearing loss, optic atrophy or neuropathy, and defective platelet aggregation resulting in peptic ulcer bleeding (summary by Mozzillo et al., 2014). For a discussion of genetic heterogeneity of Wolfram syndrome, see WFS1 (222300).

PNPLA6 disorders span a phenotypic continuum characterized by variable combinations of cerebellar ataxia; upper motor neuron involvement manifesting as spasticity and/or brisk reflexes; chorioretinal dystrophy associated with variable degrees of reduced visual function; and hypogonadotropic hypogonadism (delayed puberty and lack of secondary sex characteristics). The hypogonadotropic hypogonadism occurs either in isolation or as part of anterior hypopituitarism (growth hormone, thyroid hormone, or gonadotropin deficiencies). Common but less frequent features are peripheral neuropathy (usually of axonal type manifesting as reduced distal reflexes, diminished vibratory sensation, and/or distal muscle wasting); hair anomalies (long eyelashes, bushy eyebrows, or scalp alopecia); short stature; and impaired cognitive functioning (learning disabilities in children; deficits in attention, visuospatial abilities, and recall in adults). Some of these features can occur in distinct clusters on the phenotypic continuum: Boucher-Neuhäuser syndrome (cerebellar ataxia, chorioretinal dystrophy, and hypogonadotropic hypogonadism); Gordon Holmes syndrome (cerebellar ataxia, hypogonadotropic hypogonadism, and – to a variable degree – brisk reflexes); Oliver-McFarlane syndrome (trichomegaly, chorioretinal dystrophy, short stature, intellectual disability, and hypopituitarism); Laurence-Moon syndrome; and spastic paraplegia type 39 (SPG39) (upper motor neuron involvement, peripheral neuropathy, and sometimes reduced cognitive functioning and/or cerebellar ataxia).

Cortisone reductase deficiency (CRD) results from a failure to regenerate the active glucocorticoid cortisol from cortisone via the enzyme 11-beta-hydroxysteroid dehydrogenase (HSD11B1; 600713). The oxoreductase activity of 11-beta-HSD requires the NADPH-regenerating enzyme hexose-6-phosphate dehydrogenase (H6PD; 138090) within the endoplasmic reticulum. Lack of cortisol regeneration stimulates ACTH-mediated adrenal hyperandrogenism, with males manifesting in early life with precocious pseudopuberty and females presenting in midlife with hirsutism, oligomenorrhea, and infertility. Biochemically, CRD is diagnosed through the assessment of urinary cortisol and cortisone metabolites and consists of measuring the tetrahydrocortisol (THF) plus 5-alpha-THF/tetrahydrocortisone (THE) ratio, which in CRD patients is typically less than 0.1 (reference range, 0.7 to 1.2) (summary by Lavery et al., 2008). Genetic Heterogeneity of Cortisone Reductase Deficiency CORTRD2 (614662) is caused by mutation in the HSD11B1 gene (600713) on chromosome 1q32.

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-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).

A rare genetic endocrine disorder characterized by persistently high prolactin serum levels (not associated with gestation, puerperium, drug intake or pituitary tumor) in multiple affected family members. Clinically it manifests with signs usually observed in hyperprolactinemia, which are: secondary medroxyprogesterone acetate (MPA)-negative amenorrhea and galactorrhea in female patients, and hypogonadism and decreased testosterone level-driven sexual disfunction in male patients. Oligomenorrhea and primary infertility have also been reported in some female patients.

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).

Familial partial lipodystrophy type 4 is an autosomal dominant metabolic disorder characterized by childhood or young adult onset of loss of subcutaneous adipose tissue primarily affecting the lower limbs, insulin-resistant diabetes mellitus, hypertriglyceridemia, and hypertension (summary by Gandotra et al., 2011). Other features may include hepatic steatosis, acanthosis nigricans, polycystic ovary syndrome, and renal disease (summary by Chen et al., 2018). For a general phenotypic description and a discussion of genetic heterogeneity of familial partial lipodystrophy (FPLD), see 151660.

Autosomal recessive intellectual developmental disorder-79 (MRT79) is characterized by global developmental delay apparent from infancy. Affected individuals have mildly delayed walking with an ataxic gait and severely impaired intellectual development with poor or absent speech. Additional features may include postnatal microcephaly and dysmorphic features (Van Bergen et al., 2022).

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).