Eric. Should you be looking for a UK group, you could not go past the Oxford (Sykes) at http://www.oxfordancestors.com/index.html but world wide the Family Tree DNA in USA are the largest http://www.familytreedna.com/products.html Both these and others combine results in YSearch http://www.ysearch.org. The Latterday Saints under Sorenson will do free testing but are not yet as I understand, prepared to give actual Marker values. Interesting reading though - http://www.smgf.org/ With Dna, some finds are made but with the size of the present databases, you would be lucky to achieve good results. Peter Oxenbridge New Zealand