geometrically is there any advantage of dna being formatted as a double helix. (other than being wrapped around itself).

 

for eg) if it were a spiral would that confer any advantages?

 

Any research on this?

Well, shape follows function and the molecular machinery in cells has evolved around the conformation of DNA. The advantages are, if you will, that the shape is the stable form under physiological conditions and allows for specific binding and interaction with proteins. That is not to say that a different shape would not allow it, but it would need enzymes that currently do not exist. Also note that the helix shape is only the case for short and free DNA in solution. In cells it is often heavily coiled and does not exhibit the perfect helical shape throughout a chromosome, for example.

 

In fact, one can artificially manipulate DNA to various shapes (see DNA origami), but these of course cannot fulfill biological actions as native DNA.