Tracing Arab-Islamic inheritance in Madagascar: study of the Y-chromosome and mitochondrial DNA in the Antemoro

Abstract

Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar.

Figure 1. Repartition of the ethnic groups for which genetic data are available and that have been used in this study.

1 : Merina [5,6]; 2. Sihanaka; 3. Bezanozano; 4. Betsileo [5]; 5. Vezo; 6. Mikea [7]; 7. Antandroy; 8. Antanosy; 9. Antaisaka [6]; 10. Antemoro (this study). Populations from 1 to 4 were grouped in Highlands population.

Figure 2. Absolute frequency of NRY haplogroups in the Antemoro.

The maximum parsimony phylogeny relating the NRY haplogroups is label with markers that define them.

Figure 3. Absolute frequency of mitochonfrial haplogroups in the Antemoro.

The maximum parsimony phylogeny relating the mitochondrial haplogroups is label with markers that define them.

Figure 4. MDS plot computed from F_ST values between Malagasy populations and the Comoros based on 17 Y-STR data.

Figure 5. Principal Component Analysis plot computed from NRY haplogroup frequencies of the Antemoro and populations from the database.

The insert showed the contribution of haplogroups to the two components.

Figure 6. Median-Joining network computed from Y-STR minimal haplotypes (DYS19, DYS389i, DYS389ii, DYS390, DYS391, DYS392, DYS393) in the Antemoro and populations from various geographic regions belonging to haplogroup J1.

Circles are haplotypes. Sizes of these circles are proportional to haplotype frequency and branch lengths are proportional to number of differences between haplotypes.

Figure 7. Median-Joining network computed from Y-STR minimal haplotypes (DYS19, DYS389i, DYS389ii, DYS390, DYS391, DYS392, DYS393) in the Antemoro and populations from various geographic regions belonging to haplogroup T.

Circles are haplotypes. Size of these circle are proportional to haplotype frequency and branch lengths are proportional to number of differences between haplotypes.