Surname spellings only became fixed in the last 100-200 years. In UK lines I have people who are from the same family tree who use the spellings Cruse and Cruwys. In the US there is a big tree from Virginia and some descendants are Cruses and others are Crews. The AncestryDNA test is only available in the US. It cannot be used in the surname projects at Family Tree DNA. Family Tree DNA offer a test called Family Finder which is the same as the AncestryDNA test but provides better tools and is not reliant on being an Ancestry subscriber to have full access to your matches. We are collecting autosomal data in the Cruse project. FTDNA should soon be allowing third party transfers from Ancestry so it would be worth your while transferring your results to FTDNA once this feature becomes available.