Haplogroup

A haplogroup is a group of single chromosomes, or single DNA strands, which share a common ancestor. They have the same mutation in all versions.The technical way of saying this is: they have the same single nucleotide polymorphism (SNP) mutation in all haplotypes. 

Haplogroups show deep ancestral origins dating back thousands of years.The International Society of Genetic Genealogy see Haplogroup definition in DNA--NEWBIE GLOSSARY 

In human genetics, the haplogroups usually studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups. Both can be used to define genetic populations. Y-DNA is passed only from father to son, while mtDNA is passed only from mother to children. Neither recombines, and thus Y-DNA and mtDNA change only by chance mutations with no intermixture between parents' genetic material.

 Related pages 
J1 (Y-DNA)

 References 

Category:DNA
Category:Chromosomes