11. Gender Flashcards
(44 cards)
Elements of biology in gender
Nucleus
DNA
Chromosome
Gene
Nitrogenous bases
Adenine
Guanine
Thymine
Cytosine
Chromosomes
45 out of 46 human chromosomes are the same across males and females.
Only difference between male and female.
Epigenetics
Modifications to genes that don’t permanently change the genes.
Epi - over or above.
Over and above the genes, just altering whether they show up or not.
How epigenetics work?
Gene transcription
Repressor protein turns off gene transcription.
Activator protein increases gene transcription.
Sex differences in at least four related epigenetic parameters
DNA methylation patterns
Methyl transferases
Methyl-binding proteins
Corepressor proteins, all of which can contribute to lasting differences in the brain and behaviour.
Epigenetics is implicated in the basis of gender incongruence
Cis-gendered versus transgendered people and see if they have differences in epigenetics.
The main finding of this study is that cis and trans populations have different global CpG methylation profiles prior to GAHT. Therefore, the results suggest that epigenetics may be involved in the cause of gender incongruence.
Don’t know why people have gender dysphoria but epigenetics is providing a new possibility.
Hormones released from the hypothalamus
TRH
CRH
GHRH
Dopamine
Somatostatin
Vasopressin
Hormones released from the pineal gland
Melatonin
Hormones released from the pituitary gland
GH
TSH
ACTH
FSH
MSH
LH
Prolactin
Oxytocin
Vasopressin
Hormones released from the pancreas
Insulin
Glucagon
Somatostatin
Hormones released from the ovary
Oestrogen
Progesterone
Hormones released from the testes
Androgens
Oestradiol
Inhibin
Unisex embryos
Babies have the same sex organ until 8 weeks old.
Sex organ before it develops - could develop into either a penis or a vagina.
Wolffian duct (male)
Genital tubercle enlarges to form the penis. The male testes form high in the abdomen then descend to scrotum near term.
Mullerian duct (female)
Grow to form ovary and uterus, genital tubercle enlarges and forms the clitoris.
Four layers of sex before birth
- Chromosomal sex
Indifferent foetal sex - Differentiated foetal gonadal sex
- Foetal hormonal sex
- Genital sex
Foetal internal reproductive sex
Brain sex
Chromosomal developmental sexual disorders
Turner syndrome
Klinefelter syndrome
Mixed gonadal dysgenesis
Chromosomal ovotesticular
Turner syndrome
Genotype: 45, XO
Gonadal phenotype: Streak ovaries, no puberty, impaired fertility
Characteristics: short stature, broad chest, webbed neck
Clinical concerns: cardiac and renal concerns, lymphedema
Klinefelter syndrome
Genotype: 47, XXY
Gonadal phenotype: small testes, delayed/incomplete puberty, impaired fertility
Characteristics: Gynecomastia, reduced body/facial hair, tall stature and long extremities
Clinical concerns: Breast cancer, learning disabilities
Mixed gonadal dysgenesis
Genotype: 45 X, 46 XY
Gonadal phenotype: Streak ovary and testis, incomplete puberty, impaired fertility
Characteristics: short stature
Clinical concerns: cardiac and renal defects
Chromosomal ovotesticular
Genotype: 46 XX, 46 XY
Gonadal phenotype: Testicular and ovarian tissue present
Characteristics: Phenotype depends on gonadal hormonal functioning
Clinical concerns: Hypospadias, cryptorchidism
Hormonal DSDs - Androgen insensitivity syndrome
- Chromosomes: XY
- Gonads: testes
- Foetal hormones: testosterone
- Genitals: clitoris, vagina, labia
Baby is born XY and their body starts developing and starts to produce androgens.
Body cannot recognise the androgens.
Develop external looking genitalia but don’t have working ovaries.
After puberty can become confusing as period doesn’t start.
Go to the doctor and find out they’re biologically male.
What does intersexuality do about our understanding of a sex dichotomy?
→ Clinical levels rare; non-clinical levels more common?
→ There may be as many as 1,600,000 intersex individuals.
→ Blurs and bridges the divide between female and male.