Genetics Glossary
Use this page when a term appears in an article and you want a quick, plain-language definition.
Haplogroup
A branch on the human genetic tree defined by shared mutations inherited from a common ancestor. Haplogroups help trace deep ancestry and migration history over long time scales.
TMRCA
Time to the Most Recent Common Ancestor. An estimate of when all members of a lineage last shared one ancestor. For Y-DNA or mtDNA, it is often expressed in years before present.
aDNA (Ancient DNA)
DNA recovered from archaeological remains such as bones or teeth. It gives direct evidence of past populations and can test migration hypotheses more directly than modern DNA alone.
mtDNA (Mitochondrial DNA)
DNA inherited almost exclusively through the maternal line (mother to child). It is used to study maternal ancestry and maternal haplogroups such as H1.
Y-DNA
DNA carried on the Y chromosome, inherited through the paternal line (father to son). It is used to track paternal ancestry and paternal haplogroups such as E-M81 and E-PF2546.
Where to Apply These Terms
These definitions are used throughout the Lineage, Genetics, and Research pages.
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