Genes of Embryogenesis

Question 1

Sonic Hedgehog gene

Answer 1

Function: - Anteroposterial axis
- CNS development

Where produced: at base of limbs

Mutation: holoprosencephaly (prosencephalon fails to develop into 2 hemispheres)

Question 2

Wnt-7 gene

Answer 2

Function: Dorsal-Ventral axis

Where produced: apical ectodermal ridge (thickened ectoderm on developing limbs)

Question 3

Fibroblast growth factor (FGF) gene

Answer 3

Function: lengthening of limbs

Where produced: apical ectodermal ridge (thickened ectoderm on developing limbs)

Question 4

Homeobox (Hox) genes

Answer 4

Function: - craniocaudal direction
- code for transcription factors
Mutation: appendages in wrong location