What phenotype would you predict results if siamois and/or twin had loss of function mutations? Why?
ANSWER:
Phenotype will be formed without head
Because Loss of function of Siamois and Twin genes resulted in a loss of head structures, but trunk and tail development will be normal.
Siamois and Twin are required for head organizer function, but not for the full activity of the Spemann organizer. So while the gain-of-function and dominant repressor studies suggest that Siamois and Twin confer full organizer activity (head and trunk organizer)
What phenotype would you predict results if siamois and/or twin had loss of function mutations? Why?