Evolutionists have certainly tackled the origin of biochemical pathways for example:
Krem MM, Cera ED.
Evolution of enzyme cascades from embryonic development to blood coagulation.
Trends Biochem Sci. 2002 Feb;27(2):67-74. Review.
PMID: 11852243
The study of the evolution of many other genetic and cellular systems is still in its infancy due to the huge amount of work that is needed to dissect deveopmental pathways. Even well studied systems like sex determination have huge gaps when it comes to many protein/protein and gene/protein interactions. Working out the origin of a system is impossible unless you actually know what all the bits are and how they work!.