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Paragroup

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Paragroup is a term used in population genetics to describe lineages within a haplogroup that are not defined by any additional unique markers.

In human Y-chromosome DNA haplogroups, paragroups are typically represented by an asterisk (*) placed after the main haplogroup.[1]

The term "paragroup" is a portmanteau of the terms paraphyletic haplogroup indicating that paragroups form paraphyletic subclades.[1] Apart from the mutations that define the parent haplogroup, paragroups may not possess any additional unique markers. Alternatively paragroups may possess unique markers that have not been discovered. If a unique marker is discovered within a paragroup, the specific lineage is given a unique name and is moved out of the paragroup to form an independent subclade.

For example, the paragroup of human Y-DNA Haplogroup DE is DE*. A member of DE* has the marker that defines DE, but not the markers that define DE's only known immediate subclades, haplogroups D and E.[2] Likewise, haplogroup E1b1b1g (also known as E-M293) is an example of a relatively new subclade, discovered within a previously designated paragroup and assigned a new name. Until the SNP/UEP marker M293 was discovered in 2008, the members of the subclade were indistinguishable from other components of the paragroup E1b1b1* (also known as E3b* and E-M35*).[3]

Another example is a member of the Y-DNA haplogroup R (defined by marker M207) may belong to the sub-haplogroup R1 (defined by marker M173) or R2 (defined by marker M124). Individuals with neither of these mutations would be categorised as belonging to haplogroup R*.

References

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  1. ^ a b The Y Chromosome Consortium, T. Y. C. (2002). "A Nomenclature System for the Tree of Human Y-Chromosomal Binary Haplogroups" (PDF). Genome Research. 12 (2). Cold Spring Harbor Laboratory Press: 339–48. doi:10.1101/gr.217602. PMC 155271. PMID 11827954.
  2. ^ Weale, Michael E.; et al. (2003). "Rare Deep-Rooting Y Chromosome Lineages in Humans: Lessons for Phylogeography". Genetics. 165 (1): 229–34. doi:10.1093/genetics/165.1.229. PMC 1462739. PMID 14504230.
  3. ^ Henn, BM; et al. (2008). "Y-chromosomal evidence of a pastoralist migration through Tanzania to southern Africa". Proceedings of the National Academy of Sciences of the United States of America. 105 (31). PNAS: 10693–8. Bibcode:2008PNAS..10510693H. doi:10.1073/pnas.0801184105. PMC 2504844. PMID 18678889.


Phylogenetic tree of human mitochondrial DNA (mtDNA) haplogroups

  Mitochondrial Eve (L)    
L0 L1–6  
L1 L2   L3     L4 L5 L6
M N  
CZ D E G Q   O A S R   I W X Y
C Z B F R0   pre-JT   P   U
HV JT K
H V J T