Haplogroup BT

Haplogroup BT
Possible time of origin 70,000-80,000 years BP
Possible place of origin Africa
Ancestor A2-T
Descendants B-M60, CT
Defining mutations Page65.1/SRY1532.1/SRY10831.1, M42, M91, M94, M139, M299, P97, V21, V29, V31, V59, V64, V102, V187, V202, V216, V235

In human genetics, Haplogroup BT (BT-M91, formerly also variously known as A4, BR, or BCDEF) is a Y-chromosome haplogroup. The paragroup or haplogroup without additional lineage definition has not been found in modern populations. It is therefore known by its descendant lineages. It connects ancestral haplogroup A (more precisely, A2-T[1]) with B and CT.

Phylogenetics

The revised y-chromosome family tree by Cruciani et al. (2011) compared with the family tree from Karafet et al. (2008). Cruciani et al. (2011) define BT via M91 and P97, and as a consequence, ISOGG has listed BT since February 2012, and treated M91 as defining mutation for BT since 2014.[2]

Prior to 2002, there were in academic literature at least seven naming systems for the Y-Chromosome Phylogenetic tree. This led to considerable confusion. In 2002, the major research groups came together and formed the Y-Chromosome Consortium (YCC). They published a joint paper that created a single new tree that all agreed to use. This phylogenetic tree of haplogroup B subclades is based on the YCC 2008 tree[3]

The ISOGG tree since 2014 (and as of 2015) has treated M91 as the defining mutation of BT.[4]

See also

Genetics

Y-DNA backbone tree

Evolutionary tree of human Y-chromosome DNA (Y-DNA) haplogroups
MRC Y-ancestor
A00 A0'1'2'3'4
A0 A1'2'3'4
A1 A2'3'4
A2'3 A4=BCDEF
A2 A3 B CDEF
DE CF
D E C F
GHIJKLT
G HIJKLT
H IJKLT
IJ KLT (K)
I J LT(K1) K (K2)
L T MPS (K2b) X (K2a)
MS P NO
M S QR N O
Q R
  1. ↑ van Oven M, Van Geystelen A, Kayser M, Decorte R, Larmuseau HD (2014). "Seeing the wood for the trees: a minimal reference phylogeny for the human Y chromosome". Human Mutation 35 (2): 187–91. doi:10.1002/humu.22468. PMID 24166809.

References

  1. ↑ "A2-T" is the nomenclature of Cruciani (2011), referring to haplogroup ISOGG (2012) A1b (P108, V221).
  2. ↑ ISOGG Haplogroup A (2012): "BT is shown on this tree, though it is not considered to be a part of Haplogroup A, in order to make it clear that, as a sibling clade with A1b1 and A1b2, BT and all other haplogroups are downstream of A1b. Listed 15 February 2012." (also note that the group labelled "A1b" in the image is the "A0" of ISOGG (2012)).
  3. ↑ Karafet TM, Mendez FL, Meilerman MB, Underhill PA, Zegura SL, Hammer MF (2008). "New binary polymorphisms reshape and increase resolution of the human Y chromosomal haplogroup tree". Genome Research 18 (5): 830–8. doi:10.1101/gr.7172008. PMC 2336805. PMID 18385274. "Clade B is defined by four mutations (M60, M181, P85, and P90) and contains 17 branches with 28 internal markers (Supplemen- tal Fig. 2). This represents an increase of two defining and eight internal mutations since 2002." Supplementary Figure 2 (p. 18, "Tree corresponding to Haplogroup B") does not list M42. Supplementary Table 1 lists M42 as characteristic of haplogroup BR.
  4. ↑ Y-DNA Haplogroup A and its Subclades - 2012 (BT as subclade of A1b-P108) Y-DNA Haplogroup A and its Subclades - 2014 (BT as subclade of A1b-P108); Y-DNA Haplogroup Tree 2015 (BT-M91 listed as subclade of A1a-M31). ISOGG has listed M42 as a mutation characteristic (but not defining) of BT since 2012.