Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NEURO4850_ContemporaryTopics > Biology of Sex Differentiation, Sexual Orientation, and Gender Identity > Flashcards

Biology of Sex Differentiation, Sexual Orientation, and Gender Identity Flashcards

1
Q

Taboo Topics
Lecture Series #2
Biology of sex differentiation,
sexual orientation, and gender identity

A

ZACHARY WEIL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Sexual dimorphisms in human behavior

Men VS Women

A 
Higher in Males:
Aggresion
Schizophrenia
Visuospatial abilities
Autism

Higher in Females:
Depression
Nurturing Behavior
Verbal abilities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Sexual dimorphisms in human behavior

The BIG QUESTION

A

Nature (genes, hormones)
vs
Nurture (social factors, learning, culture) ?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Sexual dimorphisms in human behavior

-Ruth Hubbard, 1990.

A

“If a society puts half its children in dresses and skirts but warns them not to move in ways that reveal their underpants, while putting the other half in jeans and overalls and encouraging them to climb trees and play ball and other active outdoor games; if later, during adolescence, the half that has worn trousers is exhorted to “eat like a growing boy” while the half in skirts is warned to watch its weight and not get fat; if the half in jeans trots around in sneakers or boots, while the half in skirts totters about on spike heels, then these two groups of people will be biologically as well as socially different. Their muscles will be different, as will their reflexes, posture, arms, legs and feet, hand-eye coordination, spatial perception, and so on.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Patterns of Play Behavior

A

Girls tend to play in groups of 2 or 3, and with softer, brighter colored toys.
Even female monkeys prefer to play with dolls.

Male monkeys prefer to play with things like toy cars and trucks, monkeys don’t even drive!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Strategies used to understand human behavioral sex differences

A
  1. Animal models
    • Can experimentally control environmental conditions and manipulate hormonal conditions
  2. People that have undergone anomalous sexual differentiation
    • “Experiments of nature”
    Strategies used to understand human behavioral sex differences

3. Study different cultures to identify commonalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

parthenogenesis

A

Asexual reproduction in insects and some vertebrates (i.e. fish and reptiles)

◦ Only one sex (female) in parthenogenic animals
◦ All eggs genetically identical to mother

Although asexual reproduction is efficient, there is no genetic variation on which natural selection can act, creating a risk for extinction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The benefit of sexual reproduction

A

Sexual reproduction produces more genetic variation and evolutionary flexibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Relationship between sexual dimorphism and the mating system

A

Monogamous species (single mating partner) are LESS sexually dimorphic (different) than polygamous species (multiple mating partners)

Monogamous: Males don’t need to have so much more androgens, than the females because the males have much less competition.

Example:
Prairie voles are monogamous and the male & females are physically similar and both pretty nurturing to offspring.
Elks are polygamous, and the males are much bigger, have antlers, and are much more aggressive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Sexual selection favors sexual dimorphisms

A

Humans are mildly to moderately polygynous and display several sexual dimorphisms consistent with other polygynous species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Proximate questions

A

HOW do sexual dimorphisms arise?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Sexual Differentiation =

A

the process of becoming a male or female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do sexual dimorphisms arise?

A
  1. Chromosomal Sex
  2. Gonadal Sex
  3. Hormonal Sex
  4. Morphological Sex
  5. Behavioral Sex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Chromosomal Sex

A

F: XX, homogametic

M: XY, heterogametic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Gonadal Sex

A

Related to gametic sex.

  • F: ovaries, eggs
  • M: testes, sperm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Hormonal Sex

A

F: high estrogen, low androgen

M: high androgen, low estrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Morphological Sex

A

differences in body type, CNS, and effector organs (i.e., muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Behavioral Sex

A

discriminated on the basis of male and female typical behaviors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Mammalian Sexual Differentiation

A

Begins at fertilization with chromosomal sex and depends on whether the sperm that fertilizes the egg carries an X or a Y sex chromosome (Sex determination)

  • F: XX, homogametic
  • M: XY, heterogametic

Males determine the sex of the offspring; Females can only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Mammalian sexual differentiation:

Step 1: development of the gonads

A

Gonads: internal organs
◦ F: ovaries
◦ M: testes

Each individual is identical: whether XX or XY, have identical bipotential primordial gonads (germinal ridge)

◦ SRY gene on Y chromosome –> testis-determining factor (TDF) –> medulla (middle) of germinal ridge becomes testes

◦ No SRY –> no TDF –> cortex (outside) of germinal ridge becomes ovaries

Occurs approx. 6 weeks after conception

Partial expression of SRY gene -> incomplete gonadal
differentiation –> ovotestis

SRY can be express in one gonad and not the other —> testis develops on one side and an ovary on the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Mammalian sexual differentiation

Step 2: development of the accessory sex organs

A

Accessory sex organs connect gonads to outside environment

All individuals until the 3rd month have precursors to both male and female accessory sex organs

◦ Wolffian system develops into seminal vesicles, vas deferens, epididymis
◦ Müllerian sytem develops into fallopian tubes, uterus, cervix

Male development requires two hormones from the testes
◦ Testosterone promotes development of the Wolffian system
◦ Mullerian Inhibitory Hormone prevents Mullerian system from developing

Female development does NOT require hormones
◦ In the presence of ovaries or absence of gonads –> Mullerian system develops and Wolffian system regresses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Two processes at work in the typical development of the accessory sex organs

A

Masculinization:
induction of male traits (testosterone & 5α-DHT)

Demasculinization: removal of the potential for male traits

Feminization: induction of female traits

Defeminization: removal of the potential for female traits (Mullerian Inhibitory Hormone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Female development does NOT require hormones

A

Female system is low-key the default system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Males:

development of the external genitalia

A
  • penis, scrotum and testes
  • Androgens are responsible for male external genitalia, particularly 5α-dihydrotestosterone, which is converted from testosterone by the enzyme 5α-reductase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Females:

development of the external genitalia

A

labia, clitoris and outer vagina

No hormonal activity required for development of female genitalia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Standard development of the external genitalia

A

Although the two sexes are generally binary, genital development can fall anywhere along this continuum leading to ambiguous genitalia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

T —-> 5α-DHT

A

5α-reductase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Disorders of Sex Development (DSD)

A

Anomalies in the process of sexual differentiation

Result of chromosomal or hormonal abnormalities

“Experiments of nature”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

No record of viable organism that has a single Y chromosome

A

DSD: sex chromosome abnormalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Turner Syndrome

A

XO

– Female typical external
appearance and genitalia.
– Ovaries underdeveloped and don’t make steroid hormones.
– Require hormone treatment at puberty.
– Other hormonal abnormalities that slow growth as well as hearing loss, intellectual disability, kidney dysfunction.

DSD: sex chromosome abnormality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Klinefeltersyndrome

A

XXY

– Appear male but genitalia are underdeveloped
– Usually sterile because of reduced sperm production
– Gynecomastia, disproportionally long limbs
– Severe learning disabilities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

XYY

A

– Male appearance but usually sterile
– Above average height
– Below average intelligence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Congenital Adrenal Hyperplasia (CAH)

A

XY males are unaffected

Genetic (XX) females exposed prenatally to excess endogenous androgens from the adrenal glands resulting in masculinized genitalia with an ‘intersex’ appearance

Masculinization of the external genitalia in genetic females can also be caused by prenatal exposure to exogenous androgens, ex. Diethylstilbestrol (DES) or Medroxyprogesterone acetate (MPA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

5α-reductase deficiency

A
  • XY males that lack the 5-alpha-reductase enzyme which converts Testerone –> 5-alpha-dihydrotestosterone (androgen responsible for masculinization of the external genitalia)
  • Have ambiguous external genitalia, but the development of testes and accessory sex organs isn’t affected (because Testerone and Mullerian Inhibitory Hormone function normally)
  • Raised as girls but at puberty, Testosterone causes development of secondary sex characteristics and masculinization of external genitalia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Organizational/Activational Hypothesis

A

William C. Young (1899-1965)

Behavioral sex differences result from:

1) differential exposure to hormones that act early in development to organize neural circuitry underlying sexually dimorphic behaviors
2) differential exposure to sex steroid hormones later in life that activate the neural circuitry previously organized

36
Q

Young’s classic experiment

A

Mating behavior in rodents is sexually dimorphic:
◦ Females: lordosis
◦ Males: mounting

Rodent mating behavior under control of gonadal steroids

◦ Castration of adult males stops mounting behavior and Testosterone restores it . However, adult females
given Testosterone do not display increased mounting behavior (demasculinized)

◦ Removing ovaries from adult females stops lordosis which is reinstated with ovarian steroids.
However, treating castrated males with ovarian hormones does not lead to lordosis
(defeminized)

37
Q

Young’s classic experiment

Process

A

Hypothesis:
Hormonal events early in development are important for adult reproductive behavior

Experiment:
◦ Testosterone given to pregnant guinea pigs
◦ As adults, female offspring were ovarietcomized and given:
1) Estrogen+Progestins to stimulate female sexual behavior
2) given Testosterone to stimulate male sexual behavior

Results:
◦ Female guinea pigs exposed to androgens prenatally display reduced lordosis and increased mounting
◦ No effect of early androgen exposure on male sexual behavior

Conclusion:
The potential for masculine or feminine behavior is organized by early exposure to hormones

38
Q

Sensitive or Critical Period

A

A period of time when an animal is maximally sensitive to the organizing effects of hormones to permanently change morphology and/or
behavior.

Usually within the prenatal and/or perinatal period, depending on species
◦ Rats: first 10 d after birth
◦ Guinea pigs: halfway though their 69 day gestation period
◦ Humans: end of 1st trimester and first few weeks of 2nd trimester

Once the critical period has ended, no amount of hormones can have an organizational effect

39
Q

Organizational Effects of Hormones

A

Exposure to androgens in early life permanently organizes the brain to permit the later expression of masculine behavior in response to activational effects of hormones.

In the absence of androgens, the brain and behavior develop in a female-typical fashion.

40
Q

Organizational and Activational Effects of Hormones

A

In addition to mating behavior, many adult behavioral sex
differences in rats (i.e., aggression, parental behavior and emotional behavior) are organized by hormones during a critical period and activated by hormones in adulthood.

Organizational (

41
Q

Mechanism by which androgens masculinize the brain

A

Androgens play a direct role in the masculinization of the human brain

But, in many animals, aromatization of testosterone into estradiol masculinizes the brain

Depending on the species, females are protected from estradiol by:
• α-fetoprotein binds estrogen and prevents maternal estradiol from masculinizing the female brain
• The placenta

42
Q

aromatization

A

testosterone into estradiol

43
Q

Control of Ovulation

A

Gonadal function and
reproductive behavior is cyclic in females but tonic in males

Males:
Exposure to androgens
early in development permanently alters the neuronal
circuitry involved in the release of GnRH surges from the
hypothalamus forever destroying the potential for female positive feedback effects

Females: without exposure to
androgen, the neural circuitry
involved in GnRH surge
generation is spared

44
Q

Surge center=

A

Anteroventral periventricular nucleus (AVPV)

45
Q

Pulse center =

A

Medial basal hypothalamus

46
Q

Environmental Influences on Mammalian Sexual Differentiation

A
  • Intrauterine environment
  • Maternal stress
  • Differences in maternal care
  • Exposure to environmental chemicals
47
Q

Effects of the intrauterine environment

A

Female rat pups’ position in the
uterine horn can impact her
physiology and behavior as an
adult

2-M females are more aggressive, less attractive to males, and have longer ovarian cycles

48
Q

Effects of maternal stress

A 
Male offspring of mothers stressed during pregnancy:
  • Produce less androgen
  • Have impaired mating behavior
  • Have certain parts of the
nervous system that are more
female typical
  • Show more parental behavior
  • Are less aggressive
  • Exhibit demasculinized rough
& tumble play
49
Q

Effects of Maternal care

A

• Mother rats spend more time licking male pups than female
pups because they prefer the chemosensory cues associated
with male pups urine

• Mother rats who are rendered unable to smell their pups do not lick their male pups more and these males show altered patterns of male sexual behavior as adults suggesting that males require maternal licking to develop normal adult sexual behavior

• Females who are licked more as pups are more attentive
mothers later

50
Q

Endocrine disrupting chemicals (EDC)

A

mimic the effects of estrogen, androgen, or thyroid hormones

example: DDT, Atrazine, Bisphenol A (BPA)

51
Q

Atrazine

A

Commonly used herbicide

Does not affect adult frogs but modest levels affects sexual development in frogs producing
testicular abnormalities

52
Q

Bisphenol A

(BPA)

A

• Effects of EDC in humans include:

Males: Double the rate of cryptorchidism and hypospadias
(urethra opens on underside of penis) in boys, triple the rate of testicular cancer, reduced sperm counts

Females: earlier onset of puberty

53
Q

Environmental sex determination

A

No sex chromosomes in some species of reptiles

Temperature involved in sex determination

Effects of temperature can be overridden by steroids
◦ If eggs are incubated at male-producing temperatures but given estrogen, then females develop.
◦ If eggs are incubated at female producing temperatures but are given androgen, males develop.

54
Q

Sequential hermaprodites:

A

animals that begin life as one
sex then change to the other sex as adults

Seen in many species of fish in
response to their social
environment

Example: clownfish

If Mom dies, Dad becomes a female!

55
Q

Intersex

A

an individual with elements of

both sexes but most typically refers to gonads or genitals.

56
Q

Transsexual

A

an individual that believes that they are trapped in the ‘wrong’ sex.

57
Q

Sexual orientation

A

the preferred partners for romantic and sexual relationships.

58
Q

Do Genes Play a Role in Sexual
Orientation or Sexual Identity?

Homosexuality

A

The male siblings of a gay male are between 20-25% likely to be gay. Similar findings for the siblings of lesbians. (4-6%
in general population)

The dizygotic male twin of a gay male has a 15-20% chance of being gay.

Monozygotic twins have 65% concordance.

There is also evidence that gay men have more maternal-line gay male relatives. (implicates the X chromosome specifically
Xq28 but not at all clear the mechanism).

Strangely, the more older brothers an individual has the more likely that they will be
gay (chances increase by about a third with each older brother).

59
Q

Do Genes Play a Role in Sexual Orientation or Sexual Identity?

Transsexuality

A

don’t know yet…

60
Q

The Phall-o-meter

A

When bodies don’t fit into our pre-existing notions of male and female, we will force them to, even if it involves a knife.

Clitorises that are longer than .9cm and penises that are shorter than 2.5cm must be fixed

61
Q

CAIS

A

Complete androgen insensitivity syndrome

Genetic XY individuals with no ability to respond to androgen signaling.

Almost always raised as women.

Usually don’t know about the conditon until they don’t begin to menstruate.

Vast majority experience “heterosexual” orientation and don’t usually experience gender-related issues.

62
Q

5-alpha-reductase deficiency

A

Do not process testosterone into dihydrotestosterone

Recall that testosterone is a weak androgen and doesn’t signal strongly on it’s own.

XX females are usually unaware of this condition.

XY individuals are typically sexed as females at birth but often have enlarged clitorises.

At puberty, higher testosterone concentrations cause development of male secondary sex characteristics, and about 60% will choose to live as heterosexual males.

63
Q

Cloacal Exstrophy

A

Fairly rare birth defect with the bladder partially outside of the abdomen and a partially or completely absent penis

Typically (at least in the past) surgery and hormone therapy started at birth and these kids were raised as girls.

However, only about 50-60% of these individuals will elect to continue living as girls into adulthood.

64
Q

Congenital Adrenal Hyperplasia

A

Genetic mutation causes the adrenal to be unable to produce glucorticoid hormones. This leads to excess production of adrenal androgens.

Usually not detected in XY males until much later in life.
Has little or no effect on sexual differentiation or orientation

In females, this is usually detected at birth when girls have masculinized genitals.
Exogenous glucocorticoids can be given at birth to stop the process, but some brain sexual differentiation has already occurred.

This is the largest predictor of female to male transexuality with CAH girls 100-300x more likely to report transsexuality. *Still only 1-3%

65
Q

The Curious Story

of Olympian Stella Walsh

A

Stella Walsh was a dominant sprinter of the 1930s and 1940s, the winner of 41 U.S. Championships in various events.

Born in Poland, she
emigrated to America and became a high school star in Cleveland.

Competing for Poland at the 1932 Olympics she won gold in the 100-meter dash.

At the Berlin Olympics of 1936 she lost at 100 meters to her bitter rival Helen Stephens; a controversy followed when Walsh’s supporters hinted that Stephens was too fast to be a woman.
German doctors examined Stephens and announced she was truly female.

Walsh continued to compete
as an amateur until 1954 and was inducted into the U.S. Track & Field Hall of Fame in 1975.

5 years later, she was killed by a stray bullet during a robbery at a Cleveland shopping center.
An autopsy surprised everyone by showing that Walsh had male
genitals and both male & female chromosomes – a condition known as mosaicism.

66
Q

Unusual case of

David Reimer

A

Can a boy be transformed into a
girl?

Summer 1965. In a Winnipeg hospital, Janet Reimer’s gives birth to twin sons, Bruce & Brian.

But within 6 months, both boys develop difficulty urinating. The doctors suggest they be circumcised.

The doctors had chosen an unconventional method of circumcision, one in which the skin would be burned.

The procedure goes horribly wrong, and Bruce’s penis is burned so badly it can’t be repaired surgically.

The family sought help from many physicians. The Reimers saw a television profile of an American doctor and his theories on sex & gender. Dr. John Money of Johns Hopkins University argued that boys caught early enough could be raised to be girls. Nurture, not nature, determines a child’s gender, the doctor argued.
The Reimers took Bruce to Money’s clinic at Johns Hopkins.

At the age of 21 months, Bruce’s testicles were removed. What remained of his penis was left, not to interfere with his urinary tract.
When Bruce was released
from hospital, his parents were told to raise him as a girl.
The family was told not to divulge anything to anyone.
They went home with a girl they called Brenda.

Unhappy childhood, felt different, not accepted by boys or girls

When told at 14 about his
past, decided to have surgery to return being a male.
Later, he married a woman who already had children.

Ultimately, David committed suicide.

67
Q

DIRECTION OF HAIR WHORL

A

Klar (2004) reports that 30% of gay men show an anti-clockwise hair whorl, compared
with 8% of straight men.

The genetic mechanism connects with that responsible for handedness (hence hemispheric brain specialization).

68
Q

SEXUALLY DIMORPHIC NUCLEI IN THE HYPOTHALAMUS

A 
LeVay (1991) found differences
between gay and straight men
in certain nuclei in the
hypothalamus that differentiate
men & women and are
concerned with sexual behavior.

These were primarily the
interstitial nuclei of the anterior
hypothalamus (INAH-3) and the
suprachiasmic nucleus (SCN).

Because many of his post- mortem subjects had died of
AIDS, he was obliged to show
that this did not account for his
results.

69
Q

WELL CONNECTED BRAINS

A

Witelson (2008) have shown that that isthmus region of the corpus callosum (the conduit
between the two halves of
the brain) is larger in gay
than straight men.

This supports the idea that gay
men (like women) have less
structural & functional asymmetry in the brain than
straight men.

70
Q

AMYGDALA CONNECTIONS

A

Using PET & MRI scans, Savic & Lindstrom (2008) showed that the amygdala is wired more for fight-flight reactions (action) in straight men & lesbians, and more to
emotional responses such as anxiety (feelings) in gay men & straight women (see widespread connections on left side).

They also found more rightward asymmetry in
straight men (+12cc) and lesbians (+5cc), whereas the two sides were much the same volume in gay men & straight women.
71
Q

GRAY MATTER IN THE PERIRHINAL CORTEX

A

Using structural MRI,
Ponseti (2007) found that lesbian women had less gray matter in the left perirhinal cortex than heterosexual women.

In this respect, they were
more like men.

This area is involved in olfactory & visual processing, but the functional meaning of the finding is not clear.

No such differences were
found between gay & straight men.

72
Q

TASK PERFORMANCE PROFILES

A

Straight women & gay men excel in verbal fluency and memory.

Lesbians are better than straight women at spatial tasks

(Rahman, Wilson & Abrahams, 2004).

73
Q

PREPULSE INHIBITION IN LESBIAN WOMEN

A

Startle reactions (strength of eye-blink) are reduced if the startle stimulus (sudden loud noise) is preceded by a weaker version of itself.

PPI occurs less in women, but lesbian women respond more like men.

Since this is an involuntary reaction, it suggests hardwiring rather than social learning.

74
Q

FINGER RATIOS

A

Men typically have a shorter forefinger than ring finger.

In women, they are much the same or reversed.

This seems to be a marker of
exposure to prenatal testosterone.

Williams (2000) found that gay & straight men were similar in 2D:4D, but lesbians were inclined toward the male pattern.

Relationships were
stronger on the right hand
compared with the left.

There was a significant
tendency for men with older brothers to have a masculinised finger ratio regardless of their sexual orientation.

75
Q 
Harry Benjamin International Gender
Dysphoria Association (HBIGDA)

Standards of Care for Gender Identity Disorders – 2001

Eligibility Criteria for Hormone Therapy

A
  1. 18 years or older
  2. Demonstrable knowledge of social & medical risks and benefits of hormones
  3. Either
    A. Documented real life experience for at least 3 months
    OR
    B. Psychotherapy for at least 3 months
76
Q

Transgender Hormone Therapy

A

Heredity limits the tissue response to hormones

More is not always better

77
Q

Female to Male Treatment Options

A

No Hormones

Depotestosterone:
Testosterone, Enanthate, or Cypionate
100-200 mg IM q 2 wks (22g x 1 ½” needles)

Transdermal Testosterone:
Androderm or Teestoderm TTS 2.5-10mg qd

Testosterone Gel:
Androgel 50, 75, or 100 mg to skin qd

Testosterone Pellet:
Testopel- implant 6-10 pellets q month

78
Q

Testosterone Therapy

Permanent Changes

A

Increased facial and body hair
Deeper voice
Male pattern baldness
Clitoral enlargement

79
Q

Testosterone Therapy – Reversible Changes

A

Cessation of menses

Increased libido, changes in sexual behavior

Increased muscle mass / upper body strength

Redistribution of fat

Increased sweating / change in body odor

Weight gain / fluid retention

Prominence of veins / coarser skin

Acne

Mild breast atrophy

Emotional changes

80
Q

SURGICAL OPTIONS FOR FTMs

A

Mastectomy

Continue CBE/SBE on residual tissue

Hysterectomy/oophorectomy

Consider adding low dose estrogen or estrogen vaginal cream

Genital reconstruction
◦ Phalloplasty
◦ Metoidioplasty

81
Q

Male to Female Treatment Options

A

No hormones

Estrogens:
Premarin 1.25-10mg po qd or divided as bid
Ethinyl Estradiol (Estinyl) 0.1-1.0 mg po qd
Estradiol Patch 0.1-0.3mg q3-7 days
Estradiol Valerate inj. 20-60mg IM q2wks

Antiandrogen
Spironolactone 50-100 mg po bid

Progesterone
Not usually recommended

82
Q

Estrogen Treatment May Lead To

A

Breast Development

Redistribution of body fat

Softening of skin

Loss of erections

Testicular atrophy

Decreased upper body strength

Slowing or cessation of scalp hair loss

83
Q

Sex difference in masculine and feminine indexes was clear in the drawings by unaffected boys and
girls.

Their drawings do not or mostly do not contain
characteristics typical of the opposite sex.

A

Boys tend to draw mobile objects & mechanical objects with dark or cold colors and often use bird’s-eye-view composition when they draw pictures.

Girls like to draw human motifs (esp girls & women), flowers, and butterflies with light
& warm colors and tend to arrange motifs in a row on
the ground.

Analyses were made on the drawings of girls with congenital adrenal hyperplasia (CAH) and unaffected
boys & girls, using masculine and feminine indexes.

Compared with those of unaffected girls, the pictures of CAH girls more strongly showed masculine characteristics.

The feminine index for the pictures of CAH girls was significantly lower than that for unaffected girls, while the
masculine index for CAH girls was significantly higher
than that for unaffected girls.

Furthermore, the masculine
index for CAH girls was not significantly different
from that of unaffected boys.

These results suggest that
androgen exposure during fetal life may contribute to shaping masculine characteristics in children’s free drawings.

84
Q

Androgen Insensitivity Syndrome (AIS) also known as testicular feminization mutation (TFM) in rodents

A

• XY genotype

  • Gonads develop as testes which release Testosterone and Mullerian Inhibitory Hormone
  • Genetic mutation prevents the formation of androgen receptors which disrupts normal development of the Wolffian system and external genitalia

• Anti-Mullerian hormone still has a defeminizing effect

• Normal-appearing female external gentalia, female appearance and female gender identity

• Usually not discovered until puberty

85
Q

Hermaphrodites

A

Individuals who have both ovaries and testes

• Extremely rare

NEURO4850_ContemporaryTopics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions