I've blogged before about FTDNA's Hickey project. DNA 'techies' may find the latest report  from the project administrator of interest: Similar sounding surnames arose in different areas simultaneously. The Hickey surname is no exception. We have defined two definitive groups, those that only test L21 and those that test DF27. R1b-L21 is the branch of the human family tree marked by the mutation L21+. This includes all R-L21 people. It is the most common Y chromosome subclade of paternal lineages in the British Isles and is also significant in France. R1b-DF27 is the branch of the human family tree marked by the mutation DF27+. It is a very common Y chromosome clade of paternal lineages in Western Europe. There are several large subclades of R1b-DF27. The Hickey surname arose in each of these groups. Without being too scientific, L21 and DF27 probably separated about 5000 years ago. Rox2 came a few thousand years after DF27. This makes trying to match members difficult - even when we have the testing but harder without the testing as some of the branching of members goes quite a ways back... For an article on Rox2 Read momhttps://sites.google.com/site/rox2cluster/. FamilyTreeDNA has some good information on DF27 and L21. For now, my husband Bill is in his own unique category: 3d. Haplogroup R1b > L21 > CTS4466 >A195 South Irish Group 2. More testing may be helpful.