MedGen

Reduced number or density of pubic hair. [from HPO]

Absence of pubic hair. [from HPO]

17 alpha(a)-hydroxylase/17,20-lyase deficiency is a condition that affects the function of certain hormone-producing glands called the gonads (ovaries in females and testes in males) and the adrenal glands. The gonads direct sexual development before birth and during puberty and are important for reproduction. The adrenal glands, which are located on top of the kidneys, regulate the production of certain hormones, including those that control salt levels in the body. People with 17a-hydroxylase/17,20-lyase deficiency have an imbalance of many of the hormones that are made in these glands. 17a-hydroxylase/17,20-lyase deficiency is one of a group of disorders, known as congenital adrenal hyperplasias, that impair hormone production and disrupt sexual development and maturation.

Hormone imbalances lead to the characteristic signs and symptoms of 17a-hydroxylase/17,20-lyase deficiency, which include high blood pressure (hypertension), low levels of potassium in the blood (hypokalemia), and abnormal sexual development. The severity of the features varies. Two forms of the condition are recognized: complete 17a-hydroxylase/17,20-lyase deficiency, which is more severe, and partial 17a-hydroxylase/17,20-lyase deficiency, which is typically less so.

Males and females are affected by disruptions to sexual development differently. Females (who have two X chromosomes) with 17a-hydroxylase/17,20-lyase deficiency are born with normal external female genitalia; however, the internal reproductive organs, including the uterus and ovaries, may be underdeveloped. Women with complete 17a-hydroxylase/17,20-lyase deficiency do not develop secondary sex characteristics, such as breasts and pubic hair, and do not menstruate (amenorrhea). Women with partial 17a-hydroxylase/17,20-lyase deficiency may develop some secondary sex characteristics; menstruation is typically irregular or absent. Either form of the disorder results in an inability to conceive a baby (infertility).

In affected individuals who are chromosomally male (having an X and a Y chromosome), problems with sexual development lead to abnormalities of the external genitalia. The most severely affected are born with characteristically female external genitalia and are generally raised as females. However, because they do not have female internal reproductive organs, these individuals have amenorrhea and do not develop female secondary sex characteristics. These individuals have testes, but they are abnormally located in the abdomen (undescended). Sometimes, complete 17a-hydroxylase/17,20-lyase deficiency leads to external genitalia that do not look clearly male or clearly female. Males with partial 17a-hydroxylase/17,20-lyase deficiency may have a small penis (micropenis), the opening of the urethra on the underside of the penis (hypospadias), or a scrotum divided into two lobes (bifid scrotum). Males with either complete or partial 17a-hydroxylase/17,20-lyase deficiency are also infertile. [from MedlinePlus Genetics]

Bent bone dysplasia syndrome-1 (BBDS1) is a perinatal lethal skeletal dysplasia characterized by poor mineralization of the calvarium, craniosynostosis, dysmorphic facial features, prenatal teeth, hypoplastic pubis and clavicles, osteopenia, and bent long bones (Merrill et al., 2012). Genetic Heterogeneity of Bent Bone Dysplasia Syndrome BBDS2 (620076) is caused by mutation in the LAMA5 gene (601033) on chromosome 20q13. [from OMIM]

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. [from GeneReviews]

Leydig cell hypoplasia is an autosomal recessive disorder in which loss of function of the LHCGR gene in the male prevents normal sexual development. Two types of LCH have been defined (Toledo, 1992). Type I, a severe form caused by complete inactivation of LHCGR, is characterized by complete 46,XY male pseudohermaphroditism, low testosterone and high LH levels, total lack of responsiveness to LH/CG challenge, lack of breast development, and absent development of secondary male sex characteristics. Type II, a milder form caused by partial inactivation of the gene, displays a broader range of phenotypic expression ranging from micropenis to severe hypospadias. Females with inactivating mutations in the LHCGR gene display a mild phenotype characterized by defective follicular development and ovulation, amenorrhea, and infertility (review by Themmen and Huhtaniemi, 2000). Reviews Arnhold et al. (2009) noted that the clinical manifestations of female patients with hypogonadotropic hypogonadism due to isolated LH deficiency (HH23; 228300) are very similar to those of women with hypergonadotropic hypogonadism due to inactivating mutations of the LH receptor: 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 (152780) 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. [from OMIM]

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. [from OMIM]

Underdevelopment of the pubis, which together with the ilium and the ischium, is one of the three bones that make up the hip bone. [from HPO]

Müllerian aplasia and hyperandrogenism is a condition that affects the reproductive system in females. This condition is caused by abnormal development of the Müllerian ducts, which are structures in the embryo that develop into the uterus, fallopian tubes, cervix, and the upper part of the vagina. Individuals with Müllerian aplasia and hyperandrogenism typically have an underdeveloped or absent uterus and may also have abnormalities of other reproductive organs. Women with this condition have normal female external genitalia, and they develop breasts and pubic hair normally at puberty; however, they do not begin menstruation by age 16 (primary amenorrhea) and will likely never have a menstrual period. Affected women are unable to have children (infertile).

Women with Müllerian aplasia and hyperandrogenism have higher-than-normal levels of male sex hormones called androgens in their blood (hyperandrogenism), which can cause acne and excessive facial hair (facial hirsutism). Kidney abnormalities may be present in some affected individuals. [from MedlinePlus Genetics]

Infestation of the pubic hair by the pthirus pubis parasite which results in mild to intense itching and macular lesions. The parasite, also known as crab lice, is transmitted through skin to skin contact with an infected person or through direct contact with infested objects. [from NCI]

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. [from GeneReviews]

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. [from GeneReviews]

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. [from GeneReviews]

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. [from GeneReviews]

Abnormality of the growth of the pubic hair. Pubic hair is part of the secondary sexual hair, which normally ensues during puberty. [from HPO]

Abnormality of the growth of secondary sexual hair, which normally ensues during puberty. In males, secondary sexual hair usually comprises body hair, including underarm, abdominal, chest, and pubic hair. In females, secondary sexual hair usually comprises a lesser degree of body hair, most prominently underarm and pubic hair. [from HPO]

Some ectodermal dysplasias are here classified as congenital disorders characterized by abnormal development in 2 or more ectodermal structures (hair, nails, teeth, and sweat glands) without other systemic findings. Ectodermal dysplasia of the hair/nail type is a rare congenital condition characterized by hypotrichosis and nail dystrophy without nonectodermal or other ectodermal manifestations. Hypotrichosis usually occurs after birth with varying degrees of severity, ranging from mild hair loss to complete atrichia, including the loss of scalp hair, beard, eyebrows, eyelashes, axillary hair, and pubic hair. Nail dystrophy affects all 20 digits by causing short fragile nails or spoon nails (koilonychia) (summary by Lin et al., 2012). [from OMIM]

Failure to complete ossification (maturation and calcification) of the pubic bone. [from HPO]

Alopecia-intellectual disability syndrome (APMR) is a rare autosomal recessive disorder in which affected individuals show loss of hair on the scalp, absence of eyebrows, eyelashes, and axillary and pubic hair, and mildly to severely impaired intellectual development (summary by Wali et al., 2007). Genetic Heterogeneity of Alopecia-Intellectual Disability Syndrome Loci for alopecia-intellectual disability syndrome have been mapped to chromosome 3q26.2-q26.31 (APMR2; 610422) and chromosome 18q11.2-q12.2 (APMR3; 613930). APMR4 (618840) is caused by mutation in the LSS gene (600909) on chromosome 21q22. [from OMIM]

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a disorder that mainly affects the female reproductive system. This condition causes the vagina and uterus to be underdeveloped or absent, although external genitalia are normal. Affected individuals usually do not have menstrual periods due to the absence of a uterus. Often, the first noticeable sign of MRKH syndrome is that menstruation does not begin by age 16 (primary amenorrhea). People with MRKH syndrome have a female chromosome pattern (46,XX) and normally functioning ovaries. They also have normal breast and pubic hair development. Although people with this condition are usually unable to carry a pregnancy, they may be able to have children through assisted reproduction.

When only reproductive organs are affected, the condition is classified as MRKH syndrome type 1. Some individuals with MRKH syndrome also have abnormalities in other parts of the body; in these cases, the condition is classified as MRKH syndrome type 2. In this form of the condition, the kidneys may be abnormally formed or positioned, or one kidney may fail to develop (unilateral renal agenesis). Affected individuals commonly develop skeletal abnormalities, particularly of the spinal bones (vertebrae). People with MRKH syndrome type 2 may also have hearing loss or heart defects. [from MedlinePlus Genetics]