genes of embryogenesis

Question 1

homeobox (HOX) genes

Answer 1

Proteins that function as transcription factors that regulate other genes
SKELETAL morphology layout in craniocaudal direction
put limbs at correct spot on body (not on head, etc)

Question 2

HOXD-13 mutation causes

Answer 2

synpolydactyl: extra digits + fused

Question 3

what drug alters HOX expression?

Answer 3

retinoic acid (vitamin A derivative)

Question 4

Sonic Hedgehog gene

Answer 4

expressed at base of limbs in zone of polarizing activity (ZPA)
organization along craniocaudal direction (A-P)

Question 5

SHH gene mutation causes

Answer 5

holoprosencephaly (etoh does too)

Question 6

Wnt-7 gene

Answer 6

organization along dorsal-ventral axis (feet + nose in same direction)

Question 7

FGF (fibroblast growth factor) gene

Answer 7

lengthens limbs

Question 8

FGF R3 mutation causes

Answer 8

achondroplasia (short limbs)