Derived versus Ancestral is a way to identify how a given SNP value compares against a defined Genome Build. These are genetics terms and not genealogical as used in this site for genetic genealogy.
An SNP value is called derived (or positive, or colored green) if it is opposite the genome build value. For example, an A versus the original T.
An SNP value is called ancestral (or negative, or colored red) if it is the same as the genome build value. For example, an C when the original build value is a C.
This applies to more formal, SNPs and not InDels nor STRs. STRs simply have a count or numeric value. InDels one more base pairs indicated that are inserted (extra) or deleted (removed) as compared to the genome build.
The yDNA chromosomes that the genome build is based on is a man down the R1b-L20 deep branch. As such, others in that branch like our B01 group would show very few Derived values then. But Thomas Krahn (now of YSEQ and others have been working the model building process with the others to have identified SNPs, as ancestral as indicated in the phylogenetic tree. We suspect a similar thin has gone on for the mtDNA phylogenetic tree as well.
An SNP value is called derived (or positive, or colored green) if it is opposite the genome build value. For example, an A versus the original T.
An SNP value is called ancestral (or negative, or colored red) if it is the same as the genome build value. For example, an C when the original build value is a C.
This applies to more formal, SNPs and not InDels nor STRs. STRs simply have a count or numeric value. InDels one more base pairs indicated that are inserted (extra) or deleted (removed) as compared to the genome build.
The yDNA chromosomes that the genome build is based on is a man down the R1b-L20 deep branch. As such, others in that branch like our B01 group would show very few Derived values then. But Thomas Krahn (now of YSEQ and others have been working the model building process with the others to have identified SNPs, as ancestral as indicated in the phylogenetic tree. We suspect a similar thin has gone on for the mtDNA phylogenetic tree as well.