Male-Female Binary and Sex Determination

Male-Female Binary and Sex Determination

Gender/Sex/Sexuality Diversity
Usual Sex Chromosomes
XXXXY Chromosomes
More than one X = Barr Bodies
Only one X is functional in any one cell
The other(s) fold up and get out of the way at the edge of the nuclear membrane
These “extra” X’s can be seen in the microscope and counted

Do Chromosomes Matter?

* Yes, but …
* Does XX make a female?
* Does XY make a male?
* Is XO male or female?
* 1/1666 not XX or XY

Do Gonads Matter?

* Yes, but….
* Do ovaries make a female?
* Do testes make a male?
* What do ovo-testes make?

Do Hormones Matter?

* Yes, but …
* XY chromosomes
* Cells can’t “read” male hormone signals
* “Feminine” development
* “Male” or “Female”?

Conventional Sex/Gender Variables

Prefers females
Prefers males
Sexual orientation
Masculine
Feminine
Gender role
Gender identity
Assigned gender
Prostate, testes, penis, scrotum
Uterus, ovaries, clitoris vagina
Anatomy
testosterone
Estrogen/ progesterone
Hormones
Testes
Ovaries
Gonads
XY
XX
Chromosomes

MALE
FEMALE
VARIABLES
Chromosomes and Sex Determination
Gonadal Development [regulated by genes]
Embryology of internal reproductive organs
Sex Chromosomal Variation in Humans
Turner’s Syndrome: X0
Klinefelter’s Syndrome: XXY
Androgen Insensitivity or “Testicular feminization”
Baby Girl or Baby Boy?
Hormonal Virilization
Congenital Adrenal Hyperplasia
Sex determining Region of Y (SRY)
Suppression of Female Development
Some Questions….

* How can the mechanisms that lead to sexual differentiation vary?
* What might you predict might be some outcomes of such variations?
* How would you apply gender/sex based rules/laws in cases of non-standard chromosomes?

Male-Female Binary and Sex Determination.ppt