For anyone wanting to take the Roesch/Rosch genealogy to the next level, I've volunteered to coordinate a Roesch genealogy by DNA project.
A website is at
http://webpages.charter.net/roeschdnaGoals:
1) Determine if the Roesch/Rosch families in the USA are related to each other or not
2) Hopefully find Roesch relatives in Europe
DNA testing is painless, needleless and bloodless. Primarily, it is just fun. Because DNA testing for genealogy is a bit different than other types of DNA testing, the results are of limited use for all other purposes.