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Virilization
Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is a medical term commonly used in three medical and biology of sex contexts: prenatal biological sexual differentiation, the postnatal changes of typical chromosomal male (46, XY) puberty, and excessive androgen effects in typical chromosomal females (46, XX). It is also the intended result of androgen replacement therapy in males with delayed puberty and low testosterone. Prenatal virilization In the prenatal period, virilization refers to closure of the perineum, thinning and wrinkling (rugation) of the scrotum, growth of the penis, and closure of the urethral groove to the tip of the penis. In this context, ''masculinization'' is synonymous with ''virilization''. Prenatal virilization of XX fetuses and undervirilization of XY fetuses are common causes of ambiguous genitalia suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progestin-induced Virilisation
Maternal use of androgens or high doses of certain weakly androgenic synthetic progestogens (progestins) structurally related to testosterone can masculinize (virilize) the vulva of a female fetus during susceptible times in pregnancy. Some degree of fusion of the labioscrotal folds and urogenital folds and clitoral enlargement can occur if exposure occurs from the 8th through the 12th week of gestation, but only clitoral enlargement can occur if exposure occurs after the 12th week. This can in some cases result in ambiguous genitalia. Fetal masculinization of the vulva is usually due to enzyme abnormalities involved in adrenal steroid biosynthesis, resulting in congenital adrenal hyperplasia (CAH); fetal masculinization of the vulva is much less frequently due to maternal use of androgenic steroids. Fetal masculinization of the vulva due to maternal use of androgenic steroids is generally less advanced than that due to CAH, and unlike CAH, does not cause progressive viriliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perineum
The perineum (: perineums or perinea) in placentalia, placental mammals is the space between the anus and the genitals. The human perineum is between the anus and scrotum in the male or between the anus and vulva in the female. The perineum is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), including the perineal body and surrounding structures. The perineal raphe is visible and pronounced to varying degrees. Etymology The word entered English from late Latin via Greek language, Greek περίναιος ~ περίνεος ''perinaios, perineos'', itself from περίνεος, περίνεοι 'male genitals' and earlier περίς ''perís'' 'penis' through influence from πηρίς ''pērís'' 'scrotum'. The term was originally understood as a purely male body-part with the perineal raphe seen as a continuation of the scrotal septum since Virilization, masculinization causes the development of a large anogenital distance in men, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-Reductase 2 Deficiency
5α-Reductase 2 deficiency (5αR2D) is an autosomal recessive condition caused by mutations impairing the function of ''SRD5A2'', a gene located on chromosome 2 and encoding the enzyme 5α-reductase type 2 (5αR2). 5αR2 is expressed in specific tissues and catalyzes the transformation of testosterone (T) to 5α-dihydrotestosterone (DHT). DHT plays a key role in the process of sexual differentiation. This rare deficiency causes atypical sex development in genetic males (people with a 46XY karyotype), with a broad spectrum of presentations most apparent in the genitalia. Many people with 5-alpha reductase deficiency are assigned female at birth based on their external genitalia. In other cases, affected infants are assigned male at birth based on their external genitalia, often an unusually small penis (micropenis) and the urethra opening on the underside of the penis (hypospadias). Still other affected infants may be assigned either female or male at birth as their external ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defeminization
In developmental biology and zoology Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and ..., defeminization is an aspect of the process of sexual differentiation by which a potential female-specific structure, function, or behavior is changed by one of the processes of male development. See also * Sexual differentiation * Defeminization and masculinization * Virilization * Feminization References {{Reflist Sexual anatomy Zoology Physiology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y Chromosome
The Y chromosome is one of two sex chromosomes in therian mammals and other organisms. Along with the X chromosome, it is part of the XY sex-determination system, in which the Y is the sex-determining chromosome because the presence of the Y chromosome causes offspring produced in sexual reproduction to be of male sex. In mammals, the Y chromosome contains the SRY gene, which triggers development of male gonads. The Y chromosome is passed only from male parents to male offspring. Overview Discovery The Y chromosome was identified as a sex-determining chromosome by Nettie Stevens at Bryn Mawr College in 1905 during a study of the mealworm ''Tenebrio molitor''. Edmund Beecher Wilson independently discovered the same mechanisms the same year, working with Hemiptera. Stevens proposed that chromosomes always existed in pairs and that the smaller chromosome (now labelled "Y") was the pair of the X chromosome discovered in 1890 by Hermann Henking. She realized that th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenal Gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer adrenal cortex, cortex which produces steroid hormones and an inner Adrenal medulla, medulla. The adrenal cortex itself is divided into three main zones: the zona glomerulosa, the zona fasciculata and the zona reticularis. The adrenal cortex produces three main types of steroid hormones: mineralocorticoids, glucocorticoids, and androgens. Mineralocorticoids (such as aldosterone) produced in the zona glomerulosa help in the regulation of blood pressure and osmoregulation, electrolyte balance. The glucocorticoids cortisol and cortisone are synthesized in the zona fasciculata; their functions include the regulation of metabolism and immune system suppression. The innermost layer of the cortex, the zona reticularis, produces androgens that are converted to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WNT4
WNT4 is a secreted protein that, in humans, is encoded by the ''WNT4'' gene, found on chromosome 1. It promotes female sex development and represses male sex development. Loss of function may have consequences, such as female to male sex reversal. Function The WNT gene family consists of structurally related genes that encode secreted signaling proteins. These proteins have been implicated in oncogenesis and in several developmental processes, including regulation of cell fate and embryogenesis. Pregnancy WNT4 is involved in many features of pregnancy as a downstream target of BMP2. For example, it regulates endometrial stromal cell proliferation, survival, and differentiation. These processes are all necessary for the development of an embryo. Ablation in female mice results in subfertility, with defects in implantation and decidualization. For instance, there is a decrease in responsiveness to progesterone signaling. Furthermore, postnatal uterine differentiatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R-spondin 1
R-spondin-1 is a secreted protein that in humans is encoded by the ''RSPO1'' gene, found on chromosome 1. In humans, it interacts with WNT4 in the process of female sex development. Loss of function can cause female to male sex reversal. Furthermore, it promotes canonical WNT/β catenin signaling. Structure The protein has two cysteine-rich, furin-like domains and one thrombospondin type 1 domain. Function Sex development Early gonads RSPO1 is required for the early development of gonads, regardless of sex. It has been found in mice only eleven days after fertilization. To induce cell proliferation, it acts synergistically with WNT4. They help stabilize β-catenin, which activates downstream targets. If both are deficient in XY mice, there is less expression of ''SRY'' and a reduction in the amount of SOX9. Moreover, defects in vascularization are found. These occurrences result in testicular hypoplasia. Male to female sex reversal, however, does not occur because Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Male
Male (Planet symbols, symbol: ♂) is the sex of an organism that produces the gamete (sex cell) known as sperm, which fuses with the larger female gamete, or Egg cell, ovum, in the process of fertilisation. A male organism cannot sexual reproduction, reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and Asexual reproduction, asexually. Most male mammals, including male humans, have a Y chromosome, which codes for the production of larger amounts of testosterone to develop male reproductive organs. In humans, the word ''male'' can also be used to refer to gender, in the social sense of gender role or gender identity. Overview The existence of separate sexes has evolved independently at different times and in different lineage (evolution), lineages, an example of convergent evolution. The repeated pattern is sexual reproduction in isogamy, isogamous species with two or more mating types with gametes of identic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androgen
An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the development of male secondary sex characteristics at puberty. Androgens are synthesized in the testes, the ovaries, and the adrenal glands. Androgens increase in both males and females during puberty. The major androgen in males is testosterone. Dihydrotestosterone (DHT) and androstenedione are of equal importance in male development. DHT ''in utero'' causes differentiation of the penis, scrotum and prostate. In adulthood, DHT contributes to balding, prostate growth, and sebaceous gland activity. Although androgens are commonly thought of only as male Sex steroids, sex hormones, females also have them, but at lower levels: they function in libido and sexual arousal. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clitoromegaly
Clitoromegaly (or macroclitoris) is an abnormal enlargement of the clitoris that is mostly congenital; it is otherwise acquired through deliberately induced clitoral enlargement, a form of body modification, by use of anabolic steroids, in particular testosterone. It can happen as part of a gender transition. It is clinically distinguishable from normal enlargement of the clitoris seen during sexual arousal. Presentation Degree of genital ambiguity is commonly measured by the Prader classification, which ranges, in ascending order of masculinisation, from 1: ''female external genitalia with clitoromegaly'' through 5: ''pseudo-phallus looking like normal male external genitalia''. Causes Clitoromegaly is a rare condition and can be either present by birth or acquired later in life. If present at birth, congenital adrenal hyperplasia Congenital adrenal hyperplasia (CAH) is a group of Genetic disorder#Autosomal recessive, autosomal recessive disorders characterized by impaired ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androgen Insensitivity Syndrome
Androgen insensitivity syndrome (AIS) is a condition involving the inability to respond to androgens, typically due to androgen receptor dysfunction. It affects 1 in 20,000 to 64,000 XY (karyotype, karyotypically male) births. The condition results in the partial or complete inability of Animal cell, cells to respond to androgens. This unresponsiveness can impair or prevent the Development of the reproductive system, development of male genitals, as well as impairing or preventing the development of male Secondary sex characteristics, secondary sexual characteristics at puberty. It does not significantly impair female genital or sexual development. The insensitivity to androgens is therefore clinically significant only when it occurs in genetic males, (i.e. individuals with a Y chromosome, Y-chromosome, or more specifically, an SRY, SRY gene). Clinical phenotypes in these individuals range from a typical body shape, male habitus with mild spermatogenesis, spermatogenic defect or re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
