-- Sunday, 1 January 2006, at 3:21 a.m.
The X-chromosome is not used for this testing because females do receive two and at this time scientists don't know which came from the father and which from the mother. Plus that mixing your brother mentioned.
That is why the female line testing uses mtDNA which like the Y-chromosome, passes from the mother (only) virtually unchanged from one generation to the next. The mother passes the mtDNA to all her children, but only her daughters pass it to the next generation. The test subject may be male or female, but all descent back from there must be female to female.
>My female line DNA test came back as 87% European 8% Native, and 5%
The mtDNA and the Y-chromosome show only one ancestry. The result you have given is the biogeographical ancestry results which covers all of your ancestry, not your mtDNA lineage.
mtDNA reflects the ancestry from your mother's mother's mother's mother's mother on back through mothers into antiquity. It has none of the ancestry from your other thousands of ancestors, none from your mother's father, nor any of your father's ancestors.
Trace Genetics has a database of Native American groups which may be something to look into regarding your brother's Y-chromosome results.
Come on over to the DNA forum and check out the postings there.