their Nubian and Sudanese Arab samples. The authors concluded that the "Nubians can be seen as a group with substantial genetic material relating to Nilotes that later received much gene-flow from Eurasians and East Africans. The strongest admixture came from Eurasian populations and was likely quite extensive: 39.41%-47.73%." Sirak et al. (2015) analysed the DNA of a Christian-period inhabitant of Kulubnarti in northern Nubia near the Egyptian border. They found that this individual was most closely related to Middle Eastern populations. Further excavations of two Early Christian period (AD 550-800) cemeteries at Kulubnarti, one located on the mainland and the other on an island, revealed the existence of two ancestrally and socioeconomically distinct local populations. Preliminary results, including mitochondrial haplogroup analysis, suggests there may be substantial differences in the genetic composition between the two communities, with 70% of individuals from the island cemetery demonstrating African-based haplogroups (L2, L1, and L5), compared to only 36.4% of mainlanders, who instead show an increased prevalence of European and Near Eastern haplogroups (including K1, H, I5, and U1). In 2018, Carina M. Schlebusch and Mattias Jakobsson in the Annual Review of Genomics and Human Genetics, found that Nilotic populations from South Sudan (e.g. Dinka, Nuer and Shilluk) remained isolated and received little to no geneflow from Eurasians, West African Bantu-speaking farmers, and other surrounding groups. In contrast, Nubians and Arabs in the north showed admixture from Western Eurasian populations. The population structure analysis and inferred ancestry showed that "the Nubian, Arab, and Beja populations of northeastern Africa roughly display equal admixture fractions from a local northeastern African gene pool (similar to the Nilotic component) and an incoming Eurasian migrant component." Christian-Era DNA Sirak et al. 2021 obtained and analyzed the whole genomes of 66 individuals from the site of Kulubnarti situated between the 2nd and 3rd cataract and dated to the Christian period between 650 and 1000 CE. The samples were obtained from two cemeteries, R and S. Grave materials between the two cemeteries did not differ, but physical analyses of the remains found differences in morbidity and mortality indicating that the R cemetery individuals were of a higher social class than the cemetery S individuals. The study analyzed the data they obtained along with other published ancient and modern samples from Africa and West Eurasia. The genetic profile of the sampled Christian-era Nubians was found to be a mixture between West Eurasian and