同: TDF

WordNet

undergo a test; "She doesnt test well"
any standardized procedure for measuring sensitivity or memory or intelligence or aptitude or personality etc; "the test was standardized on a large sample of students" (同)mental test, mental testing, psychometric test
the act of undergoing testing; "he survived the great test of battle"; "candidates must compete in a trial of skill" (同)trial
the act of testing something; "in the experimental trials the amount of carbon was measured separately"; "he called each flip of the coin a new trial" (同)trial, run
a hard outer covering as of some amoebas and sea urchins
put to the test, as for its quality, or give experimental use to; "This approach has been tried with good results"; "Test this recipe" (同)prove, try, try out, examine, essay
achieve a certain score or rating on a test; "She tested high on the LSAT and was admitted to all the good law schools"
determine the presence or properties of (a substance)
show a certain characteristic when tested; "He tested positive for HIV"
be a contributing factor; "make things factor into a companys profitability"
any of the numbers (or symbols) that form a product when multiplied together
an independent variable in statistics
anything that contributes causally to a result; "a number of factors determined the outcome"
consider as relevant when making a decision; "You must factor in the recent developments" (同)factor in, factor out
resolve into factors; "a quantum computer can factor the number 15" (同)factor in, factor out
an event known to have happened or something known to have existed; "your fears have no basis in fact"; "how much of the story is fact and how much fiction is hard to tell"
a concept whose truth can be proved; "scientific hypotheses are not facts"
a piece of information about circumstances that exist or events that have occurred; "first you must collect all the facts of the case"
a statement or assertion of verified information about something that is the case or has happened; "he supported his argument with an impressive array of facts"
one of the two male reproductive glands that produce spermatozoa and secrete androgens; "she kicked him in the balls and got away" (同)testicle, orchis, ball, ballock, bollock, nut, egg

PrepTutorEJDIC

(人の能力などの)『試験』,考査,テスト / (物事の)『試験』,検済,試錬,実験《+of+名》 / 化学分析;試薬 / =test match / …‘を'『試験する』,検査する / …‘を'化学分析する / (…の)試験を受ける,試験をする《+for+名》
(…の)『要因』,(…を生み出す)要素《+『in』+『名』(do『ing』)》 / 囲数,約数 / 代理人,《おもに英》仲買人 / =factorize
〈C〉『事実』,実際にある(あった)事 / 〈U〉真相,真実(truth) / 《the~》(法律用語で)犯行
=testicle

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/09/19 16:47:07」(JST)

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Testis-determining factor (TDF) is a protein signal that results in maleness in humans and some other species.

Certain genes cause chemical reactions that result in the development of testes. Embryos are gonad-ally identical, regardless of genetic sex, until a certain point in development; when the testis-determining factor causes male sex organs to develop. Lack of this factor will cause the embryo to develop as physically female.^[1]

The TDF is encoded by the SRY gene located in the Y chromosome.^[2] This gene is a DNA-binding protein that enhances other transcription factors, or is a transcription factor itself. Its expression directly or indirectly causes the development of primary sex cords, which later develops to seminiferous tubules. These cords form in the central part of the yet-undifferentiated gonad, turning it into a testis. The now induced Leydig cells of the testis then start secreting testosterone while the Sertoli cells produce anti-Mullerian hormone.^[1]

Older texts discuss a role for the H-Y antigen in the control of testicular development, which was later disproved.

Role in disease[edit source | edit]

The genetic recombination of crossing over can cause TDF's gene to be transferred on to the X chromosome. In this case, the X chromosome will initiate testis development. So, regardless of whether a person has a Y chromosome, they will turn into a male. Though everything else will be developed as if it were a female (other sex-related alleles). The apparent sex will be male (a syndrome known as XX male syndrome).

On the converse, such a cross-over event also can result in a Y chromosome that is missing the Sex-Determining Region (SRY), which codes for TDF, replaced with the corresponding sequence from the end of the X chromosome. Individuals that inherit this Y chromosome will develop as females, despite having the normal male chromosomal set of one X and one Y. This is called Swyer syndrome (46 XY, genotypic male but phenotypic female).^[3]

References[edit source | edit]

^ ^a ^b Mittwoch, Ursula (22 October 1988), "The race to be male", New Scientist 120 (1635): 38–42
^ Berta P, Hawkins JR, Sinclair AH, Taylor A, Griffiths BL, Goodfellow PN, Fellous M (1990). "Genetic evidence equating SRY and the testis-determining factor". Nature 348: 448–450.
^ "SRY".

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Liu PY, Du GD, Zhao YX, Mu YS, Zhang AQ, Qin ZF, Zhang XY, Yan SS, Li Y, Wei RG, Qin XF, Yang YJ.SourceCollege of Chemistry and Environmental Science, Hebei University, Baoding, Hebei, China.
Chemosphere.Chemosphere.2011 Aug;84(7):972-8. Epub 2011 Jun 14.
To investigate bioaccumulation, maternal transfer and elimination of polybrominated diphenyl ethers (PBDEs) in amphibians, we collected adult frogs (Rana limnocharis) from a rice field in an e-waste recycling site in China. We found that ∑PBDEs in the whole frogs and various tissues (brain, liver,
PMID 21676430

DMRT1 prevents female reprogramming in the postnatal mammalian testis.

Matson CK, Murphy MW, Sarver AL, Griswold MD, Bardwell VJ, Zarkower D.Source1] Developmental Biology Center and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis 55455, Minnesota, USA [2] Molecular, Cellular, Developmental Biology, and Genetics Graduate Program, University of Minnesota, Minneapolis 55455, Minnesota, USA.
Nature.Nature.2011 Jul 20. doi: 10.1038/nature10239. [Epub ahead of print]
Sex in mammals is determined in the fetal gonad by the presence or absence of the Y chromosome gene Sry, which controls whether bipotential precursor cells differentiate into testicular Sertoli cells or ovarian granulosa cells. This pivotal decision in a single gonadal cell type ultimately controls
PMID 21775990