Test 1 Flashcards
(89 cards)
WT-1
Wilms tumor related gene
Expressed in the developing genital ridge, kidney, and gonads
Deletions/mutations a/w gonadal dysgenesis and predilection for Wilms tumor and nephropathy
Wilms tumor
Most common renal malignancy of early childhood (ages 2-4)
Contains embryonic glomerular structures
P/w large, palpable unilateral flank mass and/or hematuria
Loss of function mutations of tumor suppressor genes WT1 or WT2 on Chr 11
SF-1
Steroidogenic factor
Regulates genes involved in gonadal & adrenal development, steroidogenesis, and reproduction –> HELPS MAKE THE TESTES
SF-1 deletions can cause gonadal dysgenesis, adrenal failure, and persistent Müllerian structures
SOX-9
Target of SRY
With SF-1, elevates levels of anti-Mullerian hormone
Deletions or mutations –> severe skeletal dysplasia; gonadal dysgenesis in 75%
WNT-4
Inhibits SOX-9 = anti-testes
β-catenin
In females
- directly binds transcription factors
- regulated by Wnt
- regulates the formation of different body regions during development
Double DAX-1
On the X Chr. If there’s just one gene (XY karyotype), doesn’t do anything. If 2 (= XX), inhibits SRY activation of SOX9.
What hormones are being produced in a male fetus at 8 weeks, and by what cells?
Testosterone, by the Leydig cells
AMH, by the Sertoli cells
What do the Mullerian ducts become?
Fallopian tubes, midline uterus, & upper portion of the vagina
What do the Wolffian ducts become?
Epididymis, vas deferens, & seminal vesicles
Hypospadias indicate lack of what hormone?
Testosterone & particularly DHT - you need normal amounts to form the penile urethra
What stimulates Leydig cell production of testosterone during gestation?
1st trimester: hCG (acts like LH)
Rest: hypothalamic-pituitary-gonadal axis - baby’s own LH stimulates Leydig cells
What happens with exposure of female infants to androgen before 13 weeks gestation? After 13 weeks?
Before 13 weeks: can get urogenital sinus, vagina attached to urethra & without separate opening
After 13 weeks: only clitoromegaly
21-hydroxylase deficiency - clinical features
CAH, leads to virilization of females
Get hyperpigmentation, hyponatremia/hyperkalemia (can be life-threatening in first 2-3 weeks of life)
Uterine didelphys
Failure of fusion of ducts
Defects at level of vagina = longitudinal vaginal septum, which may or may not be obstructive.
Failure of fusion at level of cervix = two uterine horns (didelpys) and two cervices.
Failure of fusion above cervix = two uterine horns (didelpys).
Fetal survival >55%
Unicornuate uterus
Unilateral elongation of duct
Renal agenesis on the same side as the missing duct occurs in about 40% of
cases.
Probably because of poor vascularity, reproductive potential is poor with a
spontaneous abortion rate of about 50%.
What structures form the vagina?
Upper 2/3: Mullerian ducts
Lower 1/3: urogenital sinus
Failure of fusion: transverse vaginal septum
What’s another name for Mullerian ducts?
Paramesonephric ducts
What is a rudimentary horn?
Partial ductal elongation defect - thus, a rudimentary horn is on one side of the uterus. Defined by whether they contain endometrial tissue & whether they communicate w/ uterus or not
Cavitary rudimentary horn
Defined by the presence of functional endometrial tissue. Pregnancies can implant in this tissue, and if they do not communicate with the rest of the uterus, catastrophic results can ensue (rupture, maternal death). They should thus be surgically removed.
Bicornuate uterus
A uterus composed of two horns separated by a septum (“heart-shaped”)
Communicating endometrial cavities
Fetal survival 60%
Sertoli cells produce what hormone?
Estrogen
What are the four phases of spermiogenesis?
- Golgi phase
- Cap phase
- Acrosomal phase
- Maturational phase
Golgi phase
First stage of spermiogenesis
Large acrosomal vesicles are created by the Golgi apparatus.
