Genetics, Egypt, and History: Interpreting Geographical Patterns of Y Chromosome Variation1
Keita, S. O. Y., Boyce, A. J., History In Africa
Modern Egypt, the site of Africa's earliest state, lies near the crossroads of two other continents, and has had historic interactions with all its neighboring regions. This alone would make it an ideal place to study historical population biology. Egypt can also be conceptualized as a linear oasis in the eastern Sahara, one that traverses several regions of Africa. An oasis can be a way station or serve as a refugium, as well as be a place of settlement with its own special biological and cultural adaptive strategies. Both of these perspectives-crossroads and oasis/refugium-can be expected to provide insight into the processes that could have affected the Nile valley's populations/peoples. From these vantage points this presentation will examine aspects of what might be called the historical genetics of the Nile valley, with a focus on the Y chromosome. The time-frame is the late pleistocene through holocene; within this there are different levels of biocultural history. Of special interest here is patterns of north-south variation in the Egyptian Nile valley.
Bidirectional clinal variation in Egypt for various p49a,f Taql Y RFLP haplotypes (Table 1) has been suggested to be likely related to specific military campaigns during and after the Middle Kingdom (Lucotte and Mercier 2003a). The events considered to have brought together northern and southern populations having different Y genetic profiles are: the Egyptian campaigns against and/or colonization of lower Nubia during the Middle and New Kingdoms (respectively primarily Dynasty XII, ca. 1991-1785 BCE, and Dynasty XVIII, beginning ca. 1490 BCE); the Nubian conquest of Egypt by the Napatan kingdom that created Dynasty XXV (ca. 730-655 BCE), centered near the fourth cataract (in the Republic of the Sudan); the conquest of Egypt during the Greco-Roman period by southern Europeans; and the migration of Arabic-speaking peoples from the Near East, and much later the Turks from Anatolia, both during the Islamic period. The first two of these have been suggested to explain the pattern of the three most common haplotypes: V, XI, and IV.
The object of this paper is to examine and discuss further the observed patterns in Egypt for the p49a,f Taql RFLP variants, based on current available data. This will be accomplished in two ways-by examining haplotype frequencies in adjacent regions and by exploring data relevant to understanding the probable haplotype spatial variation in the Nile valley and its causes, beyond the events of the Middle Kingdom and afterwards. It is important to consider the issue of the original frequencies and origins of these variants in Egypt and other parts of Africa, as well as the adjacent regions. This is especially important given the ongoing tendency in some disciplines to label the Nile valley as Middle Eastern, in a fashion that effectively suggests that Egypt has no African context, and that also hides its biocultural Africanity in pre-Islamic times.
The approach taken here is to examine early Egypt from multiple disciplines in order to construct the most likely "narrative" that accounts for the facts as currently understood. It situates Egypt in a larger geographical and biogeographical context. The evidence to be primarily considered derives from published human biological studies, historical linguistics, and archeology. Although this presentation is not offered as a critique of previous literature, some repetition of published findings will be necessary for review, clarity, and emphasis.
The term Taq comes from Thermus aquaticus, a bacterium that lives in extremely hot temperatures, and whose enzymes have proved valuable in techniques used to analyze DNA for population studies-techniques that sometimes require high temperatures. The Taql endonuclease, an enzyme, cleaves DNA at particular points. Various molecular instruments called probes, that use endonucleases, can be constructed to detect variations in segments of DNA. …