I wrote about DNA as a common design element, and I thought I should try and expand on it a bit. As I hope we all know, DNA codes for proteins. It does this using a triplet of bases called a codon. We are taught that there is a single genetic code – each triplet codes for the same amino acid (or for “stop”) in all organisms. But this (as with a lot of things we are taught) is wrong. There are actually a lot of variations on this code (e.g. look at the NCBI’s database). This is a problem for evolutionists. If an organism is using one genetic code, how can it change? It cannot one day have AGA code for argenine, and the next day change to be a “stop” codon. What about all those proteins that want an argenine where it says AGA? They all have to change at the same time!
Even worse for materialists, both codes occur in the same organism – this is the difference between human nuclear DNA and mitochondrial DNA. No doubt some story can be concocted to explain how this could have happened, but common design provides a simpler explanation. We can understand that a designer might want to have slightly different code for different parts of an organism (to stop the two interfering), or that different codes are optimal in different species. We see that common design is the better explanation.