Therefore is the name of it called Babel;
because the LORD did there confound the language of all the earth:
and from thence did the LORD scatter them abroad upon the face of all the earth.
Genesis 11:9
"Historical records indicate that Aryans from Iran were the first to occupy Afghanistan (eighth century B.C.) followed by Persians (sixth century B.C.), Greeks (fourth century B.C.), Mauryans 
The official languages of Afghanistan, Dari and Pashto, are of Indo-European origin and are spoken by the Tajiks and Pathans or Pashtuns, respectively. Pathans live primarily south of the Hindu Kush Mountains and comprise the most prevalent ethnic group in Afghanistan (42%) while representing approximately 15% of the population of neighboring Pakistan.
Blood samples were obtained with informed consent from 190 unrelated males representing the general population of Pathans from Afghanistan. The collection was subsequently divided along the Hindu Kush Mountain Range into north Afghanistan (n=44) and south Afghanistan (n=146) to assess the role of the massif as a barrier and/or corridor to gene flow between the two regions.
Y-SNP and Y-STR genotyping
A total of 116 bi-allelic markers were hierarchically genotyped as previously described. The nomenclature followed for the Y-SNP haplogroup assignment is in accordance with the Y Chromosome Consortium and subsequent updates. The 17-loci Y-STR haplotype data from our previous reports were utilized in the current investigation to perform pertinent Y-STR-based analyses.
Distribution of Y-chromosome haplogroups
From a total of 116 binary markers typed, we identified 25 paternal lineages in 190 Afghan males, 11 of which were observed in north Afghanistan and 22 in the southern collection.The majority of the Afghan individuals examined in the current investigation belong to haplogroup R-M207 (67.4%), with sub-haplogroup R1a1a*-M198 predominating in both the north (50%) and south (65.8%).
Haplogroup L-M20 (9.5%), the second most abundant in this study, exhibits substantial disparity in its distribution on either side of the Hindu Kush range, with 25% of the northern Afghans belonging to this lineage, compared with only 4.8% of males from the south.
Haplogroup G-M201, which occurs at an average frequency of 7.9% in the Afghan gene pool, is reported at high frequencies in the Caucasus (eg, 74% in Ossetians from Digora) and it is thought to be associated with the Neolithic expansion throughout the region. Although G2c-M377 is the second most frequent haplogroup in south Afghanistan (6.2%), it is found at substantially lower levels in the northern population (2.3%).
South Afghanistan is represented by 22 polymorphic binary markers, 14 of which are absent from the northern region, suggesting reduced genetic diversity in the latter population. A plausible explanation for the reduced diversity might be the presence of the Hindu Kush Mountain range, which may have served as a directional barrier to gene flow.
Pakistan displays higher haplotype variance (0.548) than India (0.118), suggesting that L-M20 most likely originated in what is today Pakistan rather than in India.
Afghanistan populations are comparable to those computed for Pakistan and higher than India at the seven-loci resolution.
This finding supports the notion that the L3-M357 sub-clade is of Afghani or Pakistani origin and subsequently spread southernly to India.
Our study demonstrates close genetic ties between Pathans from Afghanistan and Pakistan. The affinity between Pathans from these two regions is expected considering that the Durand Line, which established Afghanistan southeastern limits since 1893, was imposed without concern to tribal and ethnic affiliations.
On the origins of Pathans
Although Greeks and Jews have been proposed as ancestors to Pathans, their genetic origin remains ambiguous. The Lasithi Plateau isolate, in the highlands of eastern Crete, partitions relatively close to the Afghanistan populations in the CA graph, which could be attributed to the elevated proportion of R1a1a chromosomes shared among them. However, the absence of the predominantly Greek E1b1b1a2 -V13 lineage in Pathans does not argue for genetic contributions from Greece. Ashkenazi Levites and our north and south Afghanistan populations, on the other hand, exhibit significantly higher frequency of the R1a1a-M198 haplogroup (51.7%, 50.0% and 65.8%, respectively), whereas lower frequencies are detected in Ashkenazi Cohanims (1.3%) and Ashkenazi Israelites (4.0%).
Overall, Ashkenazi Jews exhibit a frequency of 15.3% for haplogroup R1a1a-M198. Nebel et al proposed, on the basis of moderate to high frequency of R1a1a in Central Asia and southern Russia/Ukraine, that these R1a1a chromosomes in Ashkenazi groups might represent vestiges of Khazars. It is thought that this Turkic tribe from Central Asia had converted to Judaism at the end of the Eighth century A.D. and, after the fall of their kingdom, they spread and were assimilated by the emerging Ashkenazi community in Eastern Europe.
In addition, the Jewish traditions (particularly circumcision, a talith prayer shawl, shabbat, praying in the direction of Jerusalem during the Day of Atonement or Yom Kippur and the Magen David symbol in their houses, among several others) observed among Pathans from Afghanistan and the presence of haplogroup G2c-M377, a lineage commonly observed among the Ashkenazi Jewish population (~7%), are congruent with the above-stated hypothesis.
The diversity of Y-chromosome haplogroups in the Afghanistan populations examined in this study reflects the history of the area signaling multiple migrations over thousands of years. Our results indicate that Afghanistan exhibits patrilineal elements from the Neolithic revolution dispersal across Central Asia. The observed haplogroup distribution suggests some degree of genetic isolation of the northern population, likely because of the Hindu Kush Mountain range acting as a barrier and separating them from the southern Afghans who have greater contact with neighboring Pakistan and migrants from the Indian subcontinent and Central Asia.
Genetic signatures of South Central Asian populations are evident in their patrilineages and may represent gene flow associated with the Silk Road migrations. In addition, the high frequencies of R1a1a-M198 chromosomes and the sharing of seven Y-STR loci haplotypes among Pathans, Ashkenazi Jews and west Russians may represent vestiges from the Khazars of Central Asia that converted to Judaism at the end of the Eighth century A.D., connecting Pathans with certain Ashkenazi Jews by the way of a common Khazar ancestry." EuropeanJournalOfHumanGenetics