ΜΕΓΑΛΗ ΕΡΕΥΝΑ ΣΟΚ ΣΤΟ ΕΛΛΗΝΙΚΟ DNA :Greek DNA Detailed Analysis of the Genetic Results for the Greek Population

Η ΣΧΕΤΙΚΗ ΕΡΕΥΝΑ ΕΙΝΑΙ ΣΤΑ ΑΓΓΛΙΚΑ. ΥΠΑΡΧΕΙ ΒΕΒΑΙΑ ΚΑΙ Η ΔΥΝΑΤΟΤΗΤΑ 

ΜΕΤΑΦΡΑΣΗΣ ΣΤΟ GOOGLE

Christos Karatzios, Costas D. Triantaphyllidis.

Multiple Autosomal Gene Markers

In the "The History and Geography of
 Human Genes" Cavalli-Sforza, Menozzi 
and Piazza (47)grouped Greeks with other
 European and Mediterranean populations  
based on 88 to 120 loci (FIG.22. ,FIG.23 , 
FIG.24 ). Furthermore in this analysis of 
Europeans based on 88 

genes, Cavalli-Sforza, Menozzi, and Piazza
 show that Sardinians and the Lapps of Finland

 form extreme outlier groups among Europeans. 
Greeks, Basques, and Finns are also  outliers among the Europeans. They explain that in
 this case outliers implies that all the ....   

other European populations are related to these peoples which form the borders of the 

genetic structure in Europe (FIG.24). They also clearly state that Greeks are some of the 

earliest contributors of genetic material to the rest of the Europeans as they are one of the 

oldest populations in Europe (54)

FIG. 22 - From Cavalli-Sforza et al. (1994) "The History and Geography of Human Genes" [47], page 82, Figure 2.3.5. Principal-component map of the 42 populations. Greeks cluster with the Europeans (upper right corner).

FIG. 23 - From Cavalli-Sforza et al. "The History and Geography of Human Genes" [47],

 page 268, figure 5.5.1. Genetic tree of 26 European populations. Greeks grouped with 

other European and Mediterranean populations. Fst distances are based on an average 

of 88 genes. [Fixation index (Fst) is a measure of population differentiation, genetic

 distance, based on genetic polymorphism data, such as single-nucleotide polymorphisms (SNPs) or microsatellites.]

FIG. 24 - From Cavalli-Sforza et al. "The History and Geography of Human Genes" [47],

 page 269, figure 5.5.2. Principal component map of Caucasoids: N, C, and S denote

 Northern, Central, and Southern Europeans. All European populations are related to 

Greeks, Basques, and Finns, which form the borders of the genetic structure in Europe.

Ayub et al. [48] published a study where they used 182 autosomal microsatellite

 markers and 168 individuals representing 19 different human populations. The aim

 was to determine the genetic relationship of these populations (FIG.25). Ayub et al. 

concluded that:

African and non-African populations do not cluster together.

Greeks cluster with other North-European and South-European populations (like Italians) 

and are close to the Basques.

Japanese cluster with other Southeast Asian groups (e.g. Chinese, Cambodians), and

 with Pacific and New World native peoples.

San (Bushmen) are some of the earliest peoples in Africa. The origins of humankind can

 be traced to Sub-Saharan Africa. This is in agreement with a more recent worldwide 

population study of 938 people from 51 human populations using 650.000 autosomal 

single-nucleotide polymorphism loci to construct a worldwide population dendrogram(62)

FIG. 25 - From Ayub et al. [48], figure 2. Neighbor-joining tree, representing 

relationship between 19 modern human populations. Tree is based on Das genetic

 distances for 182 tri- and tetranucleotide microsatellite repeats. Bootstrap resampling 

values are provided at each fork. Greeks cluster with the Europeans.

Auton et al. [49] using 443,434 autosomal single-nucleotide polymorphisms (SNPs) and 

3,845 individuals representing four continental regions, determined that:

Greeks cluster genetically with 41 other Europeans populations tested.

Greeks were quite different genetically from Mexicans, Indians and Pakistanis (subcontinent),

 and southeast Asians.

Bauchet et al. [51] studied the genetic relationship of European (including 8 Greeks),

 North and Sub-Saharan African, Armenian, Middle Eastern, Indian and Central Asian 

populations using 9,724 autosomal single-nucleotide polymorphisms (SNPs). They

 repeated the statistical analysis using two different approaches (principal coordinate 

analysis/PCoA, and the Structure software program). Both times they determined that:

Greeks cluster closest to other European and Mediterranean peoples.

Greeks do not cluster with Sub-Saharan peoples.

FIG. 26 - From Novembre et al. [53], figure 1a. Population structure within Europe. The 

authors used 1,387 Europeans (for whom they have high confidence of individual origins) 

and 197,146 autosomal single-nucleotide polymorphisms (SNPs) for the construction of 

this graph showing their genetic pattern. It resembles very much the geographic map of

 Europe. Neighboring populations cluster close to each other, while being distinguishable. 

The Iberian peninsula, the Italian peninsula, southeastern Europe, Cyprus and Turkey can be

 recognized on the graph.

Two studies (Oscar Lao et al. [52] and Novembre et al. [53]) were published in 2008 

documenting the genetic relatedness of 2,514 and 1,387 Europeans respectively. They

 included 51 [52] and 8 [53] Greeks respectively from Macedonia (Northern Greece). They 

used 309,790 and 197,146 autosomal single-nucleotide polymorphisms (SNPs) for the 

construction of the map, respectively and had the following results:

Greeks are closest to Italians, Romanians (small sample size) and Former Yugoslavians 

[52], and to Albanians, southern Balkan Slavs, Romanians, Bulgarians, and Italians [53]

 (FIG.26).

Vardar Slavs cluster very close to Bulgarians [53] (FIG.26).

Y and mitochondrial gene markers studies

The genes contained on the Y chromosome and in mitochondrial DNA can be used to

 trace one's origins through genealogical lineages [16,34,39,42]. The combination of 

genes are classified into groups called haplogroups. The Y chromosome is transmitted

 from fathers to sons and a patrilineal lineage can be determined using this. The 

mitochondria are small structures that provide energy to all cells and they contain their

 own DNA. They are transmitted in a matrilineal manner and therefore matrilineal tracing 

can be done using their DNA. The Y chromosomal and mitochondrial haplogroups can be 

used as markers to trace a person's ethnic origins [33,34,39].

FIG. 27 - From King et al. [55], figure 3. Principal component factor analysis of Middle

 Eastern and South East European population affinities from the gene pool of Y-chromosome

 haplogroup frequencies. Greeks cluster with Middle Eastern and South East European 

populations. (G1-G3 data points indicate three geographic regions in Greece. T1-T9 data

 points indicate nine geographic regions in Turkey). Egypt, Oman and the Bedouin samples

 from the Negev tend to form an isolated cluster, distinct from the Greek data.

a) Y chromosomal gene marker studies:

Population genetic studies using Y DNA haplogroup analysis show that Greeks do indeed 

share similar backgrounds as the rest of the Europeans and especially southern Europeans

 (Italians, and southern Balkan populations) [33,55,56,57,58,59,60,61]. A few conclusions 

can be drawn from all these studies:

Greeks cluster with other Europeans [33,55,56,57,58].

Y-haplogroup E originated in Africa. Y DNA haplogroups E3b, J2 and G belonged to

 the early farmers that arrived in Europe from the Middle East, while haplogroup I represents 

the old farmers. Thus, the I, E3b, G and J haplogroups are some of the oldest Y DNA genes

 seen in Europe [33]. The R subhaplogroups are attributed to repeated ancient human population migrations into Europe. They are seen throughout Europe.

Similar to European peoples, classical sub Saharan Y chromosomal haplogroups are no

t seen in the Greek population. The African type E haplogroups seen in the Oromo and 

Amhara peoples of Ethiopia are virtually not existent among Europeans, although some 

E subhaplogroups are shared by sub Saharans and Europeans [58]. In this regard, and

 in contrast to Arnaiz-Villena's and Hajjej's conclusions, Greeks and sub Saharan people 

do not cluster together genetically in modern times [55,58] (FIG.27).

The I haplogroup is spread in all European populations with variable frequencies [60,61],

 albeit at lower frequencies in southern Europe (including Italians and Greeks).

The J haplotype is not common in Slavic peoples being practically non-existant in Croats. 

However, the J haplogroup - a genetic marker for early farming - is seen in high frequencies

 in Albanians (28%), Greeks (21,3%) Vardar Slavs (20%), Bulgarians (12%) and Turks (38%)

 [33,58].

Greeks carry signature haplogroups (G, J) with some regions in Greece showing very high 

concentrations of such genes (some regions have the highest in the World: for example the 

J2 type of the J haplogroup in Crete) [60]: The J2 type haplogroup concentrates highest in

 Southern Greece (almost 45% in Crete to almost 15% in Northern Greece) [33,60]. Other 

J subhaplogroups also show a south-north gradation in Greece [58].

Greeks (especially in northwest Greece) as well as southern Italians, and Albanians carry

 the E haplotype at high concentrations (20 - 25%) [58,59,61]. Greek signature E haplogroups

 have been seen in Southern Italy [58,59].

The frequency of the E haplogroup is lower in Vardar Slavs (15%) than in Greeks (24%) [61].

The frequency of the R1b haplogroup is similar among the Balkan populations (Croatians, 

Yugoslavs, Vardar Slavs and Greeks), but is considerably lower than in western European 

populations [61].

The R1a haplogroup type is most commonly seen among eastern European peoples. This

 type can also be seen in populations in the Middle East (modern Iraq and Iran) [63]. The R1a

 haplogroup type can be seen in low frequencies in some areas of mainland Greece (northern

 more than southern). However, Vardar Slavs commonly carry this type at frequencies much

 higher (35%) than that seen in Greeks (5 - 25%), Albanians (10%), Italians (0 -10%), and other 

western Europeans [33,61]. In this regard, the Vardar Slavs are similar to other Slavic people

 like Croatians, Slovenes, Czechs, Slovaks, Ukrainians, and Poles) [33,61]. According to Wiik,

 the Vardar Slavs, Slovenes, and Croats originate mostly from the "R1a Ukrainian area" 

compared to other Balkan peoples [33].

According to Underhill et al. [34], the Japanese (as well as other populations) do show some 

similar Y chromosomal mutations to African Y chromosomal genes, thereby supporting an

 African origin of all humans. However, in stark contrast to Arnaiz-Villena et al. [4,5], they 

cluster with other South East Asian populations when looking at the non-African signature 

mutations that their Y chromosomes carry.

b) Mitochondrial DNA Gene Markers:

MtDNA is widely accepted as a marker for tracing the evolution of humans out of Africa and

 into Europe and the rest of the World using a matrilineal line – the original mtDNA being

 termed "the mitochondrial Eve" [38]. Various studies have been performed using mtDNA 

to establish genetic relationships between populations [41,42,43,44]. Like Y chromosoma

l DNA, it too is classified into haplogroups with various peoples having certain haplogroups.

 There are also African and non-African haplogroups that have been identified. Examples 

include haplogroup H (non-African European) and L (Sub-Saharan African). Conclusions drawn

 from such studies [41,42,43,44] are summarized as follows:

Greeks group with other southern (Italian), and southeastern (Balkan) European peoples

 in a Mediterranean Europe cluster [42,43,44].

African mtDNA haplogroups can be seen in most European populations. Once analyzed,

 northwestern and central Europe falls on one end of the spectrum (less African contribution) 

while the Middle and Near East falls towards the opposite end (more African contribution).

 Greece (along with other south/southeastern Europeans falls somewhere in the middle [42,43].

In a very comprehensive study, 125 Greeks from Macedonia (60 from Thessaloniki, and 

65 pastoral Sarakatsanoi from other Macedonian Greek cities and provinces) contributed

 their mitochondrial DNA along with nearly 3,000 other European, Middle Eastern, and 

North African peoples [43]. This study clearly clusters the Greeks along with other Balkan

 peoples (Albanians) in an Eastern Mediterranean group. Haplogroup H was the most

common European haplogroup seen. Interestingly, no Sub-Saharan African L haplogroups

 were seen among Greeks in this study.

Achilli et al. studied the frequency of mtDNA from various populations from Europe (the

 Balkans, Mediterranean, Central and Northern Europe), the Caucasus, and the Middle

East. The study included Greeks from the mainland, Crete, Rhodes, and Lemnos. Based 

on the mtDNA, the Greeks clustered very closely with southern Italians, and were close to

 the other Balkan population studied: the Bulgarians [44].

The H haplogroup was seen in highest frequency, whereas the Sub-Saharan L haplogroup 

was seen in 0.4% of the studied Greeks (average European L frequency has been 

determined to be generally < 1%) [41,44].

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