Haplogroup L2

Haplogroup L2
Possible time of origin	68,100-111,100 YBP
Possible place of origin	East Africa
Ancestor	L2'3'4'6
Descendants	L2a'b'c'd, L2e
Defining mutations	146, 150, 152, 2416, 8206, 9221, 10115, 13590, 16311!, 16390

In human mitochondrial genetics, Haplogroup L2 is a human mitochondrial DNA (mtDNA) haplogroup. Its subclade L2a is some what frequent and widespread mtDNA cluster in Africa, as well as in the African diaspora Americans (19%).(Salas 2002) et al.

It is particularly abundant in Chad and the Kanembou (38% of the sample), but is also relatively frequent in Nomadic Arabs (33%). [Cerny et al. 2007]

Origin

L2 is an Africa lineage. It is believed to have evolved between 87,000 to 107,000 years ago. Its age and widespread distribution and diversity across the continent makes its exact origin point within Africa difficult to trace with any confidence. Several L2 haplotypes observed in Guineans and other West Africa populations shared genetic matches with East Africa and North Africa.

Distribution

L2 is found in approximately one third of Africans and their recent descendants.

Subclades

L2 has five main subgroups: L2a, L2b, L2c, L2d and L2e. The most common L2 sub group is Haplogroup L2a, both in Africa and the Levant .

Haplogroup L2a

Haplogroup L2a is wide spread in Africa and the most common and widely distributed sub-Saharan African Haplogroup and is also somewhat frequent at 19% in the Americas among descendants of Africans (Salas et al., 2002).

It is particularly abundant in Chad (38% of the sample).

This subclade is characterised by mutations at 2789, 7175, 7274, 7771, 11914, 13803, 14566 and 16294. It represents 62% of the total L2 and is the only subclade of L2 to be widespread all over Africa.

The wide distribution of L2a and diversity in Africa makes identifying a geographical origin difficult. The main puzzle is the almost ubiquitous Haplogroup L2a, which may have spread East and West along the Sahel Belt in North Africa after the Last Glacial Maximum, or the origins of these expansions may lie earlier, at the beginnings of the Later Stone Age, ∼40,000 years ago.

In East Africa L2a was found 15% in Nile Valley- Nubia, 5% of Egyptians, 14% of Cushite speakers, 15% of Semitic Amhara people, 10% of Gurage, 6% of Tigray-Tigrinya people, 13% of Ethiopians, 5% of Yemenis and 33% in Mozambique.

Haplgroup L2a also appears in North Africa, with the highest frequency 20% Tuareg, Fulani (14%). Found also among some Algeria Arabs , it is found at 10% among Moroccan Arabs, some Moroccan Berbers and Tunisian Berbers. (watson 1997) et al., (vigilant 1991) et al. 1991.

Haplogroup L2a1

L2a can be further divided into L2a1, harboring the transition at 16309 (Salas et al. 2002).

The most extensive pan-African haplotype (16189 16192 16223 16278 16294 16309 16390) is in the L2a1 haplogroup.

This sequence is observed in West Africa among the Malinke, Wolof, and others; in North Africa among the Maure/Moor, Hausa, Fulbe, and others; in Central Africa among the Bamileke, Fali, and others; in South Africa among the Khoisan family including the Khwe and Bantu speakers; and in East Africa among the Kikuyu from Kenya. Closely related variants are observed among the Tuareg in North Africa and West Africa and among the East African Dinka and Somali People. (Ely et. al. 2006; Watson et al. 1997)

All Ethiopian {L2} lineages can be seen as derived from the two subclades { L2a1 and L2b }

L2a1 is defined by mutations at 12693, 15784 and 16309. Most Ethiopian L2a1 sequences share mutations at nps {16189 and "16309″} However, whereas the majority (26 out of 33) "African Americans" share Haplogroup {L2a} complete sequences could be partitioned into four subclades by substitutions at nps {L2a1e-3495, L2a1a-3918, L2a1f-5581, and L2a1i-15229″}. None of those sequences, were observed in Ethiopian {"16309″} L2a1 samples. (salas 2002) et al.

Matrilineal Ancestry of Ashkenazi Jewry: Haplogroup L2a1: A Portrait of a Recent Founder Event, displays the small frequency of L2a1/L2a1f {Doron M. Behar, Ene Metspalu, Toomas Kivisild,} 2006.

Haplogroup L2a1a

Subclade L2a1a is defined by substitutions at 3918, 5285, 15244, and 15629.

There are two L2a clusters well represented in southeastern Africans, L2a1a and L2a1b, both defined by transitions at quite stable HVS-I positions. Both of these appear to have an origin in West Africa or North West Africa (as indicated by the distribution of matching or neighboring types), and to have undergone dramatic expansion either in South East Africa or in a population ancestral to present-day Southeastern Africans.

The very recent starbursts in subclades L2a1a and L2a2 suggest a signature for the Bantu expansions, as also suggested by Pereira et al. (2001).

L2a1a is defined by a mutation at 16286. The L2a1a founder candidate dates to 2,700 (SE 1,200) years ago. (Pereira et al. 2001). However, a prehistoric introgression of African mtDNA lineages into Eastern Europe (approximately 10 000 years ago) seems to be probable only for European- specific subclade L2a1a, defined by coding region mutations at positions 6722 and 12903 and detected in Czechs and Slovaks. It was previously known as L2a1a and found at its highest frequency in southeastern Africa. However, L2a1a, as defined by a substitution at (np 16286) (Salas et al. 2002), is now supported by a coding-region marker (np 3918) (fig. 2A) and was found in four of six Yemeni L2a1 lineages. L2a1a occurs at its highest frequency in Southeastern Africa (Pereira et al. 2001; Salas et al. 2002). Both the frequent founder haplotype and derived lineages (with 16092 mutation) found among Yemenis have exact matches within Mozambique sequences (Pereira et al. 2001; Salas et al. 2002). L2a1a also occurs at a smaller frequency in North West Africa, among the Maure and Bambara of Mali and Mauritania. (Rando et.al 1998; Maca-Meyer et.al. 2003)

http://www3.interscience.wiley.com/cgi-bin/fulltext/118548838/main.html,ftx_abs#b22

Haplogroup L2a1a1

L2a1a1 is defined by markers 6152C, 15391T, 16368C

Haplogroup L2a1b

L2a1b is defined by substitutions at 16189 and 10143. 16192 is also common in L2a1b and L2a1c; it appears in Southeastern Africa and so appears to be a marker for the Bantu expansion.

Haplogroup L2a1c

L2a1c shares mutation 16189 with L2a1b, and has its own markers at 3010 and 6663. 16192 is also common in L2a1b and L2a1c; it appears in Southeastern Africa as well as East Africa. This suggests some diversification of this clade in situ.

Positions T16209C C16301T C16354T on top of L2a1 define a small sub-clade, dubbed L2a1c by Kivisild et al. (2004, Figure 3) (see also Figure 6 in Salas et al. 2002), which mainly appears in East Africa (e.g. Sudan, Nubia, Ethiopia) and West Africa (e.g. Turkana, Kanuri).

In the Chad Basin four different L2a1c types, one or two mutational steps from the East and West African types, were identified. (Kivisild et al.) 2004. (citation on page.9 or 443) http://www3.interscience.wiley.com/cgi-bin/fulltext/117956691/PDFSTART

Haplogroup L2a1c1

L2a1c1 has a North African origin. L2a1c1 is defined by markers 198, 930, 3308, 8604, 16086

L2a1c1 haplogroup is observed among Tunisia Sephardic, Ashkenazi, Hebrews, Moroccans, Egyptians, Nubians, Yemenis etc.

Haplogroup L2b

Predominantly a West African clade, Ethiopian L2b sequences are distinguished from West African lineages by a transition at np 16145.

Haplogroup L2c

L2c is most frequent in Western Africa and may have arisen there.

Haplogroup L2d

L2d is most frequent in Western Africa and may have arisen there.

Ancient DNA

No ancient DNA has so far been retrieved from African remains, with the exception of Haplogroup L2a1, which was found in two specimens from the Southern Levant Pre-Pottery Neolithic B site at Tell Halula, Syria, dating from the period between ca. 9600 and ca. 8000 BP or 7500 - 6000 BCE.

Tree

This phylogenetic tree of haplogroup L2 subclades is based on the paper by Mannis van Oven and Manfred Kayser Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation and subsequent published research.

• Most Recent Common Ancestor (MRCA)
  • L1'2'3'4'5'6
    • L2'3'4'6
      • L2
        • L2a'b'c'd
          • L2a
            • L2a1
              • L2a1a
                • L2a1a1
                • L2a1a2
                  • L2a1a2a
                    • L2a1a2a1
                  • L2a1a2b
                • L2a1a3
              • 16189 (16192)
                • L2a1b
                  • L2a1b1
                • L2a1f
                  • L2a1f1
              • 143
                • L2a1c
                  • L2a1c1
                  • L2a1c2
                  • L2a1c3
                  • L2a1c4
                • L2a1d
                • L2a1e
                  • L2a1e1
                • L2a1h
                • 16189
                  • L2a1i
                  • L2a1j
                  • L2a1k
                  • 16192
                    • L2a1l
                      • L2a1l1
                        • L2a1l1a
                      • L2a1l2
            • L2a2
              • L2a2a
                • L2a2a1
              • L2a2b
                • L2a2b1
          • L2b'c
            • L2b
              • L2b1
                • L2b1a
                  • L2b1a2
                  • L2b1a3
            • L2c
              • L2c2
                • L2c2a
              • L2c3
          • L2d
            • L2d1
              • L2d1a
        • L2e

See also

• Genealogical DNA test
• Genetic Genealogy
• Human mitochondrial genetics
• Population Genetics
• Human mitochondrial DNA haplogroups

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

External links

• General
  • Ian Logan's Mitochondrial DNA Site
  • Mannis van Oven's Phylotree
• Haplogroup L2
  • Spread of Haplogroup L2, from National Geographic
  • Haplogroup L, from Genetree