DNA is not irreducibly complex. The whole argument of irreducible complexity is arrant nonsense. Save a few cranks, no one in the scientific field takes it seriously. Chemically, there is nothing about DNA that would lead one to believe that there is any intelligence behind it nor anything chemically unusual about it.
I can tell you right now that DNA can be reduced into Nucleobases, Deoxyribose sugar and phosphate.
Now, let’s take a nucleoubase, Thymine for example:
Thymine is a pyrimidine, a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring.
http://upload.wikimedia.org/wikiped...ture.png/558px-Thymine_chemical_structure.png
We can reduce that to atoms. Nitrogen, oxygen, hydrogen and carbon.
If you want to get technical, you can actually take that further into the subatomic realm of baryons made up of quarks and held together by bosons.
If you want to take that to the limits, it can be reduced to four fundamental force fields, the Strong Nuclear, Weak Nuclear, Electromagnetic and gravitational fields and their quanta.