edgepedia

Sex chromosome aneuploidies and sex development disorders

16 articles

45,X/46,XY mixed gonadal dysgenesis

45,X/46,XY mixed gonadal dysgenesis (MGD, 45,X0/46,XY MGD) is a rare sex chromosome DSD with mosaicism causing a dysgenetic testis on one side, a streak gonad on the other, ambiguous genitalia, Turner stigmata, and gonadoblastoma risk.

46,XX ovotesticular difference of sex development

46,XX ovotesticular DSD (46,XX ovotesticular difference of sex development, formerly true hermaphroditism): rare DSD with both testicular and ovarian tissue in a 46,XX person; about 1/20,000 births, mostly SRY negative.

46,XY difference of sex development due to 17-beta-hydroxysteroid dehydrogenase 3 deficiency

46,XY difference of sex development due to 17-beta-hydroxysteroid dehydrogenase 3 deficiency, also called 17-ketosteroid reductase deficiency, is a rare autosomal recessive condition impairing testosterone production.

46,XY ovotesticular difference of sex development

46,XY ovotesticular DSD (formerly true hermaphroditism) is a rare genetic DSD with both testicular and ovarian tissue in a 46,XY person; ambiguous genitalia, infertility, tumor risk, prevalence about 1-9 per 100,000.

46,XY partial gonadal dysgenesis

46,XY partial gonadal dysgenesis (46,XY PGD, partial testicular dysgenesis) is a rare DSD with atypical gonadal development and genital ambiguity in a 46,XY karyotype, caused by genes such as NR5A1, SRY, and NR0B1, with elevated FSH and variable tumor risk.

48,XXXY syndrome

48,XXXY syndrome (XXXY males, XXXY syndrome) is a rare sex chromosome condition in boys and men with three X chromosomes and one Y, causing intellectual disability, speech delay, tall stature, hypogonadism, and infertility.

48,XYYY syndrome

48,XYYY syndrome, also written 48 XYYY, is an extremely rare male-only sex chromosome aneuploidy with one X and three Y chromosomes, causing speech delay, tall stature, dental enamel defects, acne, and adult hypogonadism with infertility; about a dozen cases reported since 1965.

49,XXXXY syndrome

49,XXXXY syndrome (Fraccaro syndrome), a rare male sex chromosome aneuploidy with three extra X chromosomes, incidence 1:85,000-100,000 male births, causing intellectual disability, severe speech delay, hypotonia, skeletal and cardiac defects, hypogonadism, and infertility, distinct from Klinefelter syndrome.

Chondrodysplasia-difference of sex development syndrome

Chondrodysplasia-difference of sex development syndrome, or Nivelon-Nivelon-Mabille syndrome (OMIM 600092), is an extremely rare autosomal recessive HHAT-related disorder combining 46,XY complete gonadal dysgenesis with severe chondrodysplastic dwarfism, first described in 1992 in two siblings.

Frasier syndrome

Frasier syndrome (FS, OMIM 136680) is a rare WT1 intron 9 splice-site disorder causing focal segmental glomerulosclerosis, 46,XY complete gonadal dysgenesis, and high gonadoblastoma risk, distinct from Denys-Drash syndrome.

Meacham syndrome

Meacham syndrome (Meacham-Winn-Culler syndrome), a very rare 46,XY disorder of sex development with ambiguous genitalia, diaphragmatic defects, complex congenital heart and lung malformations; 13 cases reported, WT1-related, poor prognosis.

Ovotesticular disorder of sex development

Ovotesticular disorder of sex development, formerly called true hermaphroditism, is a congenital condition in which both ovarian and testicular tissue are present in the same individual.

Partial androgen insensitivity syndrome

Partial androgen insensitivity syndrome (PAIS, partial androgen resistance syndrome) is an X-linked 46,XY difference of sex development from partially functioning AR gene mutations, causing variable under-masculinization, hypospadias, infertility, and gonadal tumor risk.

Sudden infant death-dysgenesis of the testes syndrome

Sudden infant death-dysgenesis of the testes syndrome (SIDDT), also called TSPYL1-related syndrome, is a lethal autosomal recessive disorder of infants with testicular dysgenesis in 46,XY males, staccato cry, autonomic dysfunction, and death before 12 months from cardiorespiratory arrest; described mainly in Old Order Amish families.

Testicular agenesis

Testicular agenesis, also called bilateral anorchia or vanishing testis syndrome, is congenital absence of both testes in a 46,XY male with normal male genitalia, occurring in about 1 in 20,000 males, diagnosed by undetectable AMH and inhibin B with elevated FSH, and managed with testosterone replacement at puberty.

Tetragametic chimerism syndrome

Tetragametic chimerism syndrome (46,XX/46,XY chimerism, ORPHA:199310, ICD-11 LD56) is a rare disorder of sex development from fusion of two zygotes, causing ambiguous genitalia, infertility, and dual DNA profiles.