If I go from URL to URL then I am seeing a different page, not the same page. Ajax should not be limiting your ability to use unique titles and descriptions on the page.
I see that on your website you currently have one page set up for all sub content:
DNA Paternity Test - Blood or Buccal, Home use or Legal
Home Testing
Blood
Buccal
Legal Testing
Blood
Buccal
This is why your having issues with ranking. You need separate pages for the search engines to index for each of those categories regardless of you using Ajax or not.