Haplogroup A (Y-DNA)

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Haplogroup A
Time of origin
Place of origin	Africa
Ancestor	Y
Descendants	A1, A2, A3
Defining mutations	M91
Highest frequencies	Southern Sudanese (e.g. Dinka), Khoisan, Ethiopian Jews

In human genetics, Haplogroup A (M91) is a Y-chromosome haplogroup. Haplogroup A is found mainly in the Southern Nile region and Southern Africa. It represents the oldest and most diverse of the human Y-chromosome haplogroups. It is believed to be the haplogroup corresponding to Y-chromosomal Adam.

Contents 1 Distribution 2 Subclades 2.1 Tree 2.2 A-M13 2.3 A-P108 3 References 4 See also 5 External links

[edit] Distribution

Haplogroup A is common among the Southern Sudanese (53%),^[1] especially the Dinka Sudanese (62%),^[2] and Khoisan people, such as the Bushmen 12-44% presence of haplogroup A in South African Khoisan tribes. Surprisingly, this particular haplogroup was not found in a sample of the Hadzabe from Tanzania, a population traditionally considered an ancient remnant of Khoisans due to the presence of click consonants in their language.

It has also been reported in 14.6% (7/48) of an Amhara sample,^[3] 10.3% (8/78) of an Oromo sample,^[3] 13.6% (12/88) of another sample from Ethiopia,^[4] and 41% of a sample of the Beta Israel (Cruciani et al. 2002), and important percentages are also shared by Bantus in Kenya (14%, Luis et al. 2004), Iraqw in Tanzania (3/43 = 7.0% (Luis et al. 2004) to 1/6 = 17% (Knight et al. 2003)), and Fulbe in Cameroon (12%, Cruciani et al. 2002). Haplogroup A was also observed in a sample of a South Sudanese population at a frequency of 42.5% (Underhill et al. 2000).

[edit] Subclades

[edit] Tree

This phylogenetic tree of haplogroup A subclades is based on the YCC 2008 tree^[5] and subsequent published research.

• A
  • A- (M91, P97)
    • A1- (P108)
      • A1a- (M31, P82)
      • A1b- (P114)
    • A2- (M6, M14, M23, M49, M71, M135, M141, M196, M206, M212, MEH1, P3, P4, P5, P36.1, PK1, P247, P248)
      • A2a- (M114)
      • A2b- (P28)
      • A2c- (P262)
    • A3- (M32)
      • A3a- (M28, M59)
      • A3b- (M144, M190, M144, M190)
        • A3b1- (M51, P100, P291)
          • A3b1a- (P71, P102)
        • A3b2- (M13, M63, M127, M202, M219, M305)
          • A3b2a- (M171)
          • A3b2b- (M118)

[edit] A-M13

It must be noted, however, that the subclade of haplogroup A that is commonly found in East Africa and northern Cameroon (A3b2-M13) is different from those found in the Khoisan samples and only remotely related to them (it is actually only one of many subclades within haplogroup A). This finding suggests an ancient divergence.

[edit] A-P108

In 2007, seven men from Yorkshire, England sharing a distinctive surname were identified as being from the A1 subgroup of haplogroup A. It was discovered that these men had a common male-line ancestor from the 18th century, but no previous information about African ancestry was known. The A-P108 subgroup is extremely rare. In addition to the seven Yorkshire men, only 25 living carriers of the A-P108 subgroup are known, all of West African ancestry.^[6]

[edit] References

[edit] See also

Human Y-chromosome DNA (Y-DNA) haplogroups (by ethnic groups · famous haplotypes)

most recent common Y-ancestor

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A

BT

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B

CT

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CF

DE

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C

F

D

E

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G

H

IJK

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IJ

K

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I

J

L

M

NOP

S

T

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NO

P

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N

O

Q

R

[edit] External links

• African Haplogroup project at FTDNA
• Spread of Haplogroup A, from National Geographic