WordNet

infertility between hybrids
a gland in which gametes (sex cells) are produced (同)sex gland
of or relating to the gonads; "gonadal hormones"

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性腺(せん),生殖腺

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2012/03/19 13:46:08」(JST)

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Gonadal dysgenesis is a term used to describe multiple reproductive system development disorders.^[1] They are conditions of genetic origin.^[2] It is characterized by a progressive loss of primordial germ cells on the developing gonads of an embryo. This loss leads to extremely hypoplastic (underdeveloped) and dysfunctioning gonads mainly composed of fibrous tissue, hence the name streak gonads - i.e., a form of aplasia in which the ovary is replaced by a functionless tissue, as found in Turner syndrome.

It originally referred to Turner syndrome, but use of the term has expanded to cover other conditions.^[3]

Pathogenesis

During embryogenesis, without any external influences for or against, the human reproductive system is intrinsically conditioned to give rise to a female reproductive organisation. As a result, if a gonad cannot express its sexual identity via its hormones—as in gonadal dysgenesis—then the affected person, no matter whether genetically male or female, will develop external female genitalia. Internal female genitalia, primarily the uterus, may or may not be present depending on the etiology of the disorder.

In both sexes, the commencement and progression of puberty require functional gonads that will work in harmony with the hypothalamic and pituitary glands to produce adequate hormones. For this reason, in gonadal dysgenesis the accompanying hormonal failure also prevents the development of secondary sex characteristics in either sex, resulting in a sexually infantile female appearance and infertility.

Embryology

This condition will occur if there is an absence of both Mullerian inhibiting factor and testosterone. The absence of testosterone will result in regression of the Wolffian ducts; normal male internal reproductive tracts will not develop. The absence of Mullerian inhibiting factor will allow the Mullerian ducts to differentiate into the oviducts and uterus. In sum, this individual will be genotypically male (i.e., XY), yet will possess female-like internal and external reproductive characteristics.

Causes

The condition may be due to:

Turner syndrome, and its variations (i.e. mosaicism)
XX gonadal dysgenesis, also pure gonadal dysgenesis, 46, XX
Swyer syndrome, also pure gonadal dysgenesis, 46, XY
Perrault syndrome, XX gonadal dysgenesis + sensorineural hearing loss
Mixed gonadal dysgenesis
Endocrine disruptors

References

^ M. Sperling (2008). Pediatric endocrinology. Elsevier Health Sciences. pp. 667–. ISBN 9781416040903. http://books.google.com/books?id=jIxXJCxGNvAC&pg=PA667. Retrieved 27 October 2010.
^ Eberhard Nieschlag; Hermann M. Behre; Susan Nieschlag (July 2009). Andrology: Male Reproductive Health and Dysfunction. Springer. pp. 221–. ISBN 9783540783541. http://books.google.com/books?id=mEgckDNkonUC&pg=PA221. Retrieved 10 November 2010.
^ Douglas T. Carrell (15 February 2010). Reproductive Endocrinology and Infertility: Integrating Modern Clinical and Laboratory Practice. Springer. pp. 308. ISBN 9781441914354. http://books.google.com/books?id=lcBEheiufVcC&pg=PA308. Retrieved 27 October 2010.

UpToDate Contents

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1. ターナー症候群（性腺発育不全）の臨床症状および診断 clinical manifestations and diagnosis of turner syndrome gonadal dysgenesis
2. ターナー症候群（性腺発育不全）のマネージメント management of turner syndrome gonadal dysgenesis
3. 性染色体異常 sex chromosome abnormalities
4. ダウン症のスクリーニングにおける血清マーカー定量による妊娠転帰の予想 pregnancy outcomes predicted by serum markers assayed in down syndrome screening
5. 外陰部異常を有する幼児の評価 evaluation of the infant with ambiguous genitalia

English Journal

Swyer syndrome.

King TF1, Conway GS.
Current opinion in endocrinology, diabetes, and obesity.Curr Opin Endocrinol Diabetes Obes.2014 Dec;21(6):504-10. doi: 10.1097/MED.0000000000000113.
PURPOSE OF REVIEW: This review focuses on the pathogenesis, diagnosis, management and long-term outcomes of disorders of sex development, specifically women with Swyer syndrome (46,XY complete gonadal dysgenesis).RECENT FINDINGS: Recent discoveries have broadened our understanding of the complex pat
PMID 25314337

45,X/46,XY mosaicism: report on 14 patients from a Brazilian hospital. A retrospective study.

Rosa RF1, D'Ecclesiis WF2, Dibbi RP1, Rosa RC1, Trevisan P1, Graziadio C1, Paskulin GA1, Zen PR1.
São Paulo medical journal = Revista paulista de medicina.Sao Paulo Med J.2014 Dec;132(6):332-8. Epub 2014 Sep 2.
CONTEXT AND OBJECTIVE: 45,X/46,XY mosaicism, or mixed gonadal dysgenesis, is considered to be a rare disorder of sex development. The aim of our study was to investigate the clinical and cytogenetic characteristics of patients with this mosaicism.DESIGN AND SETTING: A retrospective study in a referr
PMID 25351753

Crown heights in the permanent teeth of 45,X and 45,X/46,XX females.

Pentinpuro RH1, Lähdesmäki RE, Niinimaa AO, Pesonen PR, Alvesalo LJ.
Acta odontologica Scandinavica.Acta Odontol Scand.2014 Nov;72(8):908-16. doi: 10.3109/00016357.2014.921327. Epub 2014 Jun 2.
Abstract Objective. Previous results regarding human sex chromosome aneuploidies have shown that the X and Y chromosomes affect tooth size and morphology. This study looked for the effect of sex chromosome deficiency on permanent tooth crown heights. Materials and methods. The material, from the Fin
PMID 24882680

Japanese Journal

腹腔鏡下に性腺を摘出した性染色体異常 (モザイク) の2例

福原健,万代昌紀,三木通保,藤原浩,小西郁生
日本産科婦人科内視鏡學會雜誌 = The journal of the Japan Endoscopy Society of Obstetrics and Gynecology 25(1), 272-276, 2009-09-01
… Her external genitalia and vagina were normal, but chromosomal analysis showed mosaicism of 45X/46XY which comfirmed the diagnosis of mixed gonadal dysgenesis. …
NAID 10026403517

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★リンクテーブル★

リンク元	「性腺形成異常症」「性腺形成不全」「性器発育不全」「性腺形成不全症」「性腺異形成」
拡張検索	「46,XY gonadal dysgenesis」「45,X gonadal dysgenesis」「46,XX gonadal dysgenesis」「XX pure gonadal dysgenesis」「complete gonadal dysgenesis」
関連記事	「dysgenesis」「gonadal」「gonad」