You should test more Y-chromosome DNA short tandem repeat (STR) markers when you wish to compare additional markers against others with similar results. They [...]
Yes. It is possible that a SNP will back mutate (change back). However, SNPs are slow changing. Thus, back mutations are uncommon.
No, the names in the mitochondrial DNA (mtDNA) haplogroups do not correspond with the same names in the Y-chromosome DNA (Y-DNA) haplogroups.
Family Tree DNA updates the phylogenetic tree when we have substantial evidence that there is a new branch or a new placement for a [...]
Y-Chromosome DNA (Y-DNA) haplogroups and subclades names follow the conventions of the Y-Chromosome Consortium’s (YCC). The YCC short form names haplogroups with the first letter from [...]