Step I Alpha-fetoprotein question

[Phloston]

Would someone please explain the mechanisms as to why AFP is elevated in neural tube defects and lowered in Down's and Edward's syndromes, and normal in Patau's?

The latter is particularly bizarre to me, and the former I'm most interested in.

So if someone could elaborate that would be awesome.

Since AFP apparently isn't elevated in spina bifida occulta, I'm curious as to the normal flow of AFP, etc., as I had heard it's the "fetal albumin."

Cheers,

 

[thehundredthone]

In open neural tube defects it leaks out of the CSF into the amniotic fluid. Normally AFP is excreted via the kidney.

I don't know why it's lowered in aneuploidies. I don't think the mechanism is clear.

 

[Phloston]

Anyone?

 

[ohyeahbaby]

Normally AFP is excreted via the kidney.

.

any clue why it's then elevated in liver CA?