Hi Iris, Good list to discuss DNA studies is GENEALOGY-DNA@rootsweb.com... I think understanding what the Y DNA test is, is better.. First, DNA is a complex string sort of like a ladder that twists upon its self.. and curls.. now certain areas are tested these areas are nomally called markers these markers have names.. as in STRs.(Think its Short Tantum Returns).and other names..most not all markers used for yDNA testing are named DYS (A division of STRs) but since there are more then one of these DYS markers they also get numbers... So in a 37 marker yDNA test there are 37 places that are tested... They will not be number 1 - 37.... an example of a DYS marker "DYS464" Some markers will have more then one result (answer) to the test... DYS464 normally has 4 but is know to both be null (not there) and with as many as 8.. How testing DNA either mtDNA or yDNA can help in genealogy is that you compare the answers to the tests with other people's answers to their tests.. It can not prove who you are related to.... but it will prove if you are related... and most important it will prove who you are NOT related to... It can shorten the paper trail hunt when you find someone your related to via DNA you can know for sure you are related instead of waisting years hunting a connect that does not exhist.. Now to your statements Your" We test YDNA to establish who the father(s) were". ANSWER: False the yDNA is not used for testing paternity cases.. it is an entirly different test.. uses different parts of the dna. YDNA can only point to a common ancestor not a particular father... We could test X DNA to find something about a person's parent, but if we test X DNA of a female, we would not know if that X DNA had come from her mother or from her father. ANSWER: THe Father's DNA came from either his mother or his father's mother... needing an Aunt to test hopefully getting different results for the markers used for the X STR testings... so you know where the X came from... So we don't test X DNA. ANSWER/ Some work is being done with X- STR's but much harder then Y-STR testing...yDNA... We do test mitochondrial DNA, which is different material altogether. ANSWER: All material tested for the different tests is a differnt part of DNA... Remember as of right now there is one heck of a lot of dna that is still classified as junk DNA.. (To me this just means they haven't found a use for it yet or an explanation about what it does, remember we are on the cuttuing edge of DNA studies...) This DNA material is contained outside of the nuclei of our cells --in the cells themselves, but not within the cell nucleus. This material, mtDNA, supposedly comes only from the mother --although the suggested website does not state how that can be. (can someone explain that one??) TRy the GENEALOGY-DNA mailing list not only do newbies like me read the emails/ and answer some... but some of the actual PHD's answer questions and in layman terms so you understand too.... Nelda Nelda's websites - http://freepages.folklore.rootsweb.com/~bonsteinandgilpin/ yDNA tests for Hurst, Beatty, Gilpin, Graves; all direct male relatives _________________________________________________________________ Add a Yahoo! contact to Windows Live Messenger for a chance to win a free trip! http://www.imagine-windowslive.com/minisites/yahoo/default.aspx?locale=en-us&hmtagline