Tissue Antigens February 2001, vol. 57, no. 2,   pp. 118-127

HLA genes in Macedonians and the sub-Saharan origin of the Greeks

Department of Immunology and Molecular Biology, H. 12 de Octubre, Universidad Complutense, Madrid, Spain.

HLA alleles have been determined in individuals from the Republic of Macedonia by DNA typing and sequencing. HLA-A, -B, -DR, -DQ allele frequencies and extended haplotypes have been for the first time determined and the results compared to those of other Mediterraneans, particularly with their neighboring Greeks. Genetic distances, neighbor-joining dendrograms and correspondence analysis have been performed. The following conclusions have been reached: 1) Macedonians belong to the "older" Mediterranean substratum, like Iberians (including Basques), North Africans, Italians, French, Cretans, Jews, Lebanese, Turks (Anatolians), Armenians and Iranians, 2) Macedonians are not related with geographically close Greeks, who do not belong to the "older" Mediterranean substratum, 3) Greeks are found to have a substantial relatedness to sub-Saharan (Ethiopian) people, which separate them from other Mediterranean groups. Both Greeks and Ethiopians share quasi-specific DRB1 alleles, such as *0305, *0307, *0411, *0413, *0416, *0417, *0420, *1110, *1112, *1304 and *1310. Genetic distances are closer between Greeks and Ethiopian/sub-Saharan groups than to any other Mediterranean group and finally Greeks cluster with Ethiopians/sub-Saharans in both neighbor joining dendrograms and correspondence analyses. The time period when these relationships might have occurred was ancient but uncertain and might be related to the displacement of Egyptian-Ethiopian people living in pharaonic Egypt.

Fig. 2. Correspondence analysis showing a global view of the relationship between Mediterraneans and sub-Saharan and Black African populations according to the HLA allele frequencies in three dimensions (bi-dimensional representation). HLA-DRBI allele frequencies data.

Fig. 3. Correspondence analysis showing a global view of the relationship among West Mediterraneans (green), East Mediterraneans (orange), Greeks and sub-Saharan populations (red) and Blacks (grey) according to HLA allele frequencies in three dimensions (bidimensional representation). HLA-DR and DQ (low resolution) allele frequencies data.

Table 5 shows the presence of these Greek alleles mainly in sub-Saharan populations from Ethiopia (Amhara, Oromo), Sudan (Nuba) and West Africa (Rimaibe, Fulani, Mossi).

It may be deduced from these data that sub-Saharans and Greeks share quasi-specific HLA-DRB1 alleles. The neighbor-joining tree (Fig. 1) and the correspondence analyses (Figs 2 and 3) confirm this Greek/sub-Saharan relatedness. The HLA-DRB1 genetic distances between Greeks and other Mediterraneans are shown in Table 6 and also support a sub-Saharan/Greek relatedness; genetic distances with HLA-DR and -DQ generic typings (not shown) give essentially the same results.

Our results show that Macedonians are related to other Mediterraneans and do not show a close relationship with Greeks; however they do with Cretans (Tables 3, 4, Figs 1–3). This supports the theory that Macedonians are one of the most ancient peoples existing in the Balkan peninsula, probably long before arrival of the Mycaenian Greeks (10) about 2000 B.C. Other possible explanation is that they might have shared a genetic background with the Greeks before an hypothetical admixture between Greeks and sub-Saharans might have occurred.

Much to our surprise, the reason why Greeks did not show a close relatedness with all the other Mediterraneans analyzed (Tables 5, 6 and Figs 1–3) was their genetic relationship with sub-Saharan ethnic groups now residing in Ethiopia, Sudan and West Africa (Burkina-Fasso). Although some Greek DRB1 alleles are not completely specific of the Greek/sub-Saharan sharing, the list of alleles (Table 5) is self-explanatory. The conclusion is that part of the Greek genetic pool may be sub-Saharan and that the admixture has occurred at an uncertain but ancient time.

Thus, it is hypothesized that there could have been a migration from southern Sahara which mixed with ancient Greeks to give rise to a part of the present day Greek genetic background. The admixture must have occurred in the Aegean Islands and Athens area at least.  

Also, the time when admixture occurred could be after the overthrown of some of the Negroid Egyptian dynasties (Nubian or from other periods) or after undetermined natural catastrophes (i.e.: dryness).

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http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7916320&dopt=Abstract

Mitochondrial DNA polymorphism in northern Greece.
Astrinidis A, Kouvatsi A.

Department of Genetics, Development, and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, Greece.

The polymorphism of human mitochondrial DNA (mtDNA) was studied in 118 unrelated Greeks (from northern Greece) using total blood cell DNA and the restriction enzymes HpaI, BamHI, HaeII, MspI, AvaII, and HincII. One new morph was identified for MspI (named MspI morph 18Gr) and is the result of a mutation in a previously thought monomorphic site at 104 bp. HpaI morph 1 was detected for the first time in a European sample. Also, AvaII morph 13 was observed in Greece in a frequency higher (5.93%) than that found in any other population. Eighteen mtDNA types were identified, three of which are new [86-2 (1-3-1-4-9-2), 87-2 (2-3-1-1-13-2), and 88-2 (2-1-1-18Gr-1-2)] and can be derived from already known mtDNA types by single restriction site changes. Type 57-2 (2-3-1-4-13-2), which had been previously characterized as "Italian," was found with higher frequency (4.24%) in northern Greece. The calculation of genetic distances and chi-square values through Monte Carlo simulation shows that the Greek sample does not differ from the Italian sample.
PMID: 7916320 [PubMed - indexed for MEDLINE]

Source: Mourant AE, Kopéc AC, Domaniewska-Sobczak K. The distribution of the human blood groups and other polymorphisms. London, Oxford University Press, 1976.