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Objectives: The aim of the study was to estimate HIV prevalence among persons with hepatitis B virus (HBV) infection in England and to examine associated risk factors. Methods: Persons aged ≥ 15 years with an HBV surface antigen (HBsAg) test reported to Public Health England (PHE) sentinel surveillance during 2008–2014 were linked to the PHE national HIV/AIDS database. Coinfection was defined as an HIV diagnosis prior to, or within 6 months following, a positive HBsAg test. Results: During 2008–2014, 2 149 933 persons were tested for HBsAg and 3.9% (1129 of 28 789) of HBsAg‐positive persons were HIV positive. The probable route of HIV infection was heterosexual exposure for 95.3% of female patients and 32.3% of male patients, with 61.5% of male patients reporting sex between men. Among African‐born coinfected persons, 84% probably acquired HIV there. Predictors of HIV positivity included older age [adjusted odds ratio (aOR) 1.1] and being of black ethnicity (aOR 15.5 for males; aOR 16.4 for females) or being male and of white ethnicity (aOR 8.2) compared with being female and of white ethnicity. HIV coinfection was more likely when HBV was diagnosed in sexual health (aOR 55.0), specialist liver (aOR 6.7), emergency department (aOR 5.3) and renal services (aOR 2.8) compared with general practice. Most (60.4%; 682 of 1129) coinfected persons were diagnosed with HIV infection > 6 months before HBV diagnosis. Conclusions: Persons testing positive for HBsAg had a low HIV infection rate and fell largely into two groups: those of black ethnicity with probable Africa‐acquired infections and white men who have sex with men (MSM) with probable UK‐acquired infections. Findings reinforce existing recommendations to sustain and improve both HBV testing of migrants from HBV‐prevalent countries and vaccination among HIV‐positive MSM. Findings also support blood‐borne virus testing in sexual health services and emergency departments. [ABSTRACT FROM AUTHOR]

Building longitudinal population cohorts in Africa for coordinated research and surveillance can influence the setting of national health priorities, lead to the introduction of appropriate interventions, and provide evidence for targeted treatment, leading to better health across the continent. However, compared to cohorts from the global north, longitudinal continental African population cohorts remain scarce, are relatively small in size, and lack data complexity. As infections and noncommunicable diseases disproportionately affect Africa's approximately 1.4 billion inhabitants, African cohorts present a unique opportunity for research and surveillance. High genetic diversity in African populations and multiomic research studies, together with detailed phenotyping and clinical profiling, will be a treasure trove for discovery. The outcomes, including novel drug targets, biological pathways for disease, and gene-environment interactions, will boost precision medicine approaches, not only in Africa but across the globe.

Background: Polygenic prediction studies in continental Africans are scarce. Africa's genetic and environmental diversity pose a challenge that limits the generalizability of polygenic risk scores (PRS) for body mass index (BMI) within the continent. Studies to understand the factors that affect PRS variability within Africa are required., Methods: Using the first multi-ancestry genome-wide association study (GWAS) meta-analysis for BMI involving continental Africans, we derived a multi-ancestry PRS and compared its performance to a European ancestry-specific PRS in continental Africans (AWI-Gen study) and a European cohort (Estonian Biobank). We then evaluated the factors affecting the performance of the PRS in Africans which included fine-mapping resolution, allele frequencies, linkage disequilibrium patterns, and PRS-environment interactions., Results: Polygenic prediction of BMI in continental Africans is poor compared to that in European ancestry individuals. However, we show that the multi-ancestry PRS is more predictive than the European ancestry-specific PRS due to its improved fine-mapping resolution. We noted regional variation in polygenic prediction across Africa's East, South, and West regions, which was driven by a complex interplay of the PRS with environmental factors, such as physical activity, smoking, alcohol intake, and socioeconomic status., Conclusions: Our findings highlight the role of gene-environment interactions in PRS prediction variability in Africa. PRS methods that correct for these interactions, coupled with the increased representation of Africans in GWAS, may improve PRS prediction in Africa., (© 2024. The Author(s).)

Objectives: Multimorbidity (MM) is a growing concern linked to poor outcomes and higher healthcare costs. While most MM research targets European ancestry populations, the prevalence and patterns in African ancestry groups remain underexplored. This study aimed to identify and summarise the available literature on MM in populations with African ancestry, on the continent, and in the diaspora., Design: A scoping review was conducted in five databases (PubMed, Web of Science, Scopus, Science Direct and JSTOR) in July 2022. Studies were selected based on predefined criteria, with data extraction focusing on methodology and findings. Descriptive statistics summarised the data, and a narrative synthesis highlighted key themes., Results: Of the 232 publications on MM in African-ancestry groups from 2010 to June 2022-113 examined continental African populations, 100 the diaspora and 19 both. Findings revealed diverse MM patterns within and beyond continental Africa. Cardiovascular and metabolic diseases are predominant in both groups (80% continental and 70% diaspora). Infectious diseases featured more in continental studies (58% continental and 16% diaspora). Although many papers did not specifically address these features, as in previous studies, older age, being women and having a lower socioeconomic status were associated with a higher prevalence of MM, with important exceptions. Research gaps identified included limited data on African-ancestry individuals, inadequate representation, under-represented disease groups, non-standardised methodologies, the need for innovative data strategies, and insufficient translational research., Conclusion: The growing global MM prevalence is mirrored in African-ancestry populations. Recognising the unique contexts of African-ancestry populations is essential when addressing the burden of MM. This review emphasises the need for additional research to guide and enhance healthcare approaches for African-ancestry populations, regardless of their geographic location., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The African Society of Human Genetics (AfSHG) was formed to provide a forum for human genetics and genomics scientists in Africa to interact, network, and collaborate. This is critical to facilitate development of solutions to the public health burden of many rare and common diseases across the continent. AfSHG fully supports the Black Lives Matter movement, which is dedicated to fighting racism and ensuring that society values the lives and humanity of Black people. The AfSHG would like to add its "voice" to the public outcry against racism sparked by George Floyd's death and to declare its commitment to ensuring that injustice and systematic racism, as well as abuse and exploitation of Africans and their biological material, are no longer tolerated. This is particularly relevant now as African genomic variation is poised to make significant contributions across several disciplines including ancestry, personalized medicine, and novel drug discovery. "Black Lives Matter and Black Research Matters" is AfSHG's call for the global community to support halting, and reversing, the perpetuation of exploitation of African people through neocolonial malpractices in genomic research. We also propose five key ways to curb racism in science, so that we can move forward together, with a common humanity, collectively embracing scientific endeavors.

The rapid increase in genomics research in Africa and the growing promise of precision public health (PPH) begs the question of whether African genomics has come of age and is being translated into improved healthcare for Africans. An assessment of the continent's readiness suggests that genetic service delivery remains limited and extremely fragile. The paucity of data on mutation profiles for monogenic disorders and lack of large genome-wide association cohorts for complex traits in African populations is a significant barrier, coupled with extreme genetic variation across different regions and ethnic groups. Data from many different populations are essential to developing appropriate genetic services. Of the proposed genetic service delivery models currently used in Africa-Uncharacterized, Limited, Disease-focused, Emerging and Established-the first three best describe the situation in most African countries. Implementation is fraught with difficulties related to the scarcity of an appropriately skilled medical genetic workforce, limited infrastructure and processes, insufficient health funding and lack of political support, and overstretched health systems. There is a strong nucleus of determined and optimistic clinicians and scientists with a clear vision, and there is a hope for innovative solutions and technological leapfrogging. However, a multi-dimensional approach with active interventions to stimulate genomic research, clinical genetics and overarching healthcare systems is needed to reduce genetic service inequalities and accelerate PPH on the continent. Human and infrastructure capacity development, dedicated funding, political will and supporting legislation, and public education and awareness, are critical elements for success. Africa-relevant genomic and related health economics research remains imperative with an overarching need to translate knowledge into improved healthcare. Given the limited data and genetic services across most of Africa, the continent has not yet come of 'genomics' age., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The African continent is regarded as the cradle of modern humans and African genomes contain more genetic variation than those from any other continent, yet only a fraction of the genetic diversity among African individuals has been surveyed 1 . Here we performed whole-genome sequencing analyses of 426 individuals-comprising 50 ethnolinguistic groups, including previously unsampled populations-to explore the breadth of genomic diversity across Africa. We uncovered more than 3 million previously undescribed variants, most of which were found among individuals from newly sampled ethnolinguistic groups, as well as 62 previously unreported loci that are under strong selection, which were predominantly found in genes that are involved in viral immunity, DNA repair and metabolism. We observed complex patterns of ancestral admixture and putative-damaging and novel variation, both within and between populations, alongside evidence that Zambia was a likely intermediate site along the routes of expansion of Bantu-speaking populations. Pathogenic variants in genes that are currently characterized as medically relevant were uncommon-but in other genes, variants denoted as 'likely pathogenic' in the ClinVar database were commonly observed. Collectively, these findings refine our current understanding of continental migration, identify gene flow and the response to human disease as strong drivers of genome-level population variation, and underscore the scientific imperative for a broader characterization of the genomic diversity of African individuals to understand human ancestry and improve health.

The 11th Congress of the African Society of Human Genetics (AfSHG) was held from September 16, 2018 to September 21, 2018, in conjunction with the 12th Human Heredity and Health in Africa (H3Africa) Consortium meeting in Kigali, Rwanda. The event was organized by the AfSHG in partnership with the Rwanda Society of Human Genetics and the University of Rwanda. A 2-day workshop on the application of next-generation sequencing technologies for analyzing monogenic disease in African populations was organized as part of the conference (September 22, 2018-September 23, 2018, Kigali, Rwanda). The theme of the conference was "Building skills and resources for genomics, epigenetics and bioinformatics research for Africa." The conference served as a platform to bring together members from country-specific Societies of Human Genetics, including Rwanda, Cameroon, Democratic Republic of Congo, Egypt, Mali, Senegal, and South Africa, and included 435 delegates from 38 countries, including 29 African countries that attended the conference. A major topic of discussion was how to bridge the gap between the emerging knowledge on genomics and Omics in African populations. The importance of understanding the role of genetic variation in disease causation and susceptibility among Africans was a constant theme during the meeting, as was the need to develop research infrastructure and resources to enhance healthcare systems, so that they are not left behind in the genomic revolution. It was concluded that there is a need to inspire more African scientists to train and work as investigators, clinicians, and genetic counselors in the field of human genetics in Africa. Local investments, and South-South and South-North collaboration were identified as the key drivers for the successful implementation of research and development on the continent.

Hypertension and obesity are the most important modifiable risk factors for cardiovascular diseases, but their association is not well characterized in Africa. We investigated regional patterns and association of obesity with hypertension among 30 044 continental Africans. We harmonized data on hypertension (defined as previous diagnosis/use of antihypertensive drugs or blood pressure [BP]≥140/90 mmHg/BP≥130/80 mmHg) and obesity from 30 044 individuals in the Cardiovascular H3Africa Innovation Resource across 13 African countries. We analyzed data from population-based controls and the Entire Harmonized Dataset. Age-adjusted and crude proportions of hypertension were compared regionally, across sex, and between hypertension definitions. Logit generalized estimating equation was used to determine the independent association of obesity with hypertension ( P value <5%). Participants were 56% women; with mean age 48.5±12.0 years. Crude proportions of hypertension (at BP≥140/90 mmHg) were 47.9% (95% CI, 47.4-48.5) for Entire Harmonized Dataset and 42.0% (41.1-42.7) for population-based controls and were significantly higher for the 130/80 mm Hg threshold at 59.3% (58.7-59.9) in population-based controls. The age-adjusted proportion of hypertension at BP≥140/90 mmHg was the highest among men (33.8% [32.1-35.6]), in western Africa (34.7% [33.3-36.2]), and in obese individuals (43.6%; 40.3-47.2). Obesity was independently associated with hypertension in population-based controls (adjusted odds ratio, 2.5 [2.3-2.7]) and odds of hypertension in obesity increased with increasing age from 2.0 (1.7-2.3) in younger age to 8.8 (7.4-10.3) in older age. Hypertension is common across multiple countries in Africa with 11.9% to 51.7% having BP≥140/90 mmHg and 39.5% to 69.4% with BP≥130/80 mmHg. Obese Africans were more than twice as likely to be hypertensive and the odds increased with increasing age.

The tenth conference of the African Society of Human Genetics was held in Egypt with the theme "Human Genetics and Genomics in Africa: Challenges for Both Rare and Common Genetic Disorders." Current research was presented, and we discussed visions for the future of genomic research on the African continent. In this report, we summarize the presented scientific research within and relevant to Africa as presented by both African and non-African scientists. We also discuss the current situation concerning genomic medicine and genomic research within the continent, difficulties in implementing genetic services and genomic medicine in Africa, and a road map to overcome those difficulties and meet the needs of the African researchers and patients.

Genetic variation and susceptibility to disease are shaped by human demographic history and adaptation. We can now study the genomes of extant Africans and uncover traces of population migration, admixture, assimilation and selection by applying sophisticated computational algorithms. There are four major ethnolinguistic divisions among present day Africans: Hunter-gatherer populations in southern and central Africa; Nilo-Saharan speakers from north and northeast Africa; Afro-Asiatic speakers from north and east Africa; and Niger-Congo speakers who are the predominant ethnolinguistic group spread across most of sub-Saharan Africa. The enormous ethnolinguistic diversity in sub-Saharan African populations is largely paralleled by extensive genetic diversity and until a decade ago, little was known about detailed origins and divergence of these groups. Results from large-scale population genetic studies, and more recently whole genome sequence data, are unravelling the critical role of events like migration and admixture and environmental factors including diet, infectious diseases and climatic conditions in shaping current population diversity. It is now possible to start providing quantitative estimates of divergence times, population size and dynamic processes that have affected populations and their genetic risk for disease. Finally, the availability of ancient genomes from Africa provides historical insights of unprecedented depth. In this review, we highlight some key interpretations that have emerged from recent African genome studies.

Human Heredity and Health in Africa (H3Africa) research seeks to promote fair collaboration between scientists in Africa and those from elsewhere. Here, we outline how concerns over inequality and exploitation led to a policy framework that places a firm focus on African leadership and capacity building as guiding principles for African genomics research., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Given the importance of Africa to studies of human origins and disease susceptibility, detailed characterization of African genetic diversity is needed. The African Genome Variation Project provides a resource with which to design, implement and interpret genomic studies in sub-Saharan Africa and worldwide. The African Genome Variation Project represents dense genotypes from 1,481 individuals and whole-genome sequences from 320 individuals across sub-Saharan Africa. Using this resource, we find novel evidence of complex, regionally distinct hunter-gatherer and Eurasian admixture across sub-Saharan Africa. We identify new loci under selection, including loci related to malaria susceptibility and hypertension. We show that modern imputation panels (sets of reference genotypes from which unobserved or missing genotypes in study sets can be inferred) can identify association signals at highly differentiated loci across populations in sub-Saharan Africa. Using whole-genome sequencing, we demonstrate further improvements in imputation accuracy, strengthening the case for large-scale sequencing efforts of diverse African haplotypes. Finally, we present an efficient genotype array design capturing common genetic variation in Africa.

Epidemiological evidence suggests that an adverse in utero environment is associated with an increased risk for developing adult onset diseases. The molecular mechanisms for susceptibility to chronic noncommunicable diseases are not fully understood, although recent research has proposed that epigenetic modifications play an important role in fetal programming. Genetic and environmental factors contribute to interindividual and spatiotemporal tissue-specific methylation patterns. Although the diverse environments and high genetic diversity of African populations provide unparalleled potential to investigate the effects of environmental change on the epigenetic profile in humans, only a small percentage of genomic and epigenetic studies have focused on populations from this continent. This emphasizes the need to build capacity in Africa for research that leads to an understanding of the association between genetic, epigenetic and environmental risk factors for noncommunicable diseases on the continent.

This is a report on a workshop titled 'Ethics for genomic research across five African countries: Guidelines, experiences and challenges', University of the Witwatersrand, Johannesburg, South Africa, 10 and 11 December 2012. The workshop was hosted by the Wits-INDEPTH partnership, AWI-Gen, as part of the H3Africa Consortium.

Cardiovascular diseases, principally ischaemic heart disease and stroke, are the leading causes of global mortality and morbidity. Together with other non-communicable diseases, they account for more than 60% of global deaths and pose major social, economic and developmental challenges worldwide. In Africa, there is now compelling evidence that the major cardiovascular disease (CVD) risk factors are on the rise, and so are the related fatal and non-fatal sequelae, which occur at significantly younger ages than seen in high-income countries. In order to tackle this rising burden of CVD, the H3Africa Cardiovascular Working Group will hold an inaugural workshop on 30 May 2014 in Cape Town, South Africa. The primary workshop objectives are to enhance our understanding of the genetic underpinnings of the common major CVDs in Africa and strengthen collaborations among the H3Africa teams and other researchers using novel genomic and epidemiological tools to contribute to reducing the burden of CVD on the continent.

Pigmentation disorders span the genetic spectrum from single-gene autosomal recessive disorders such as oculocutaneous albinism (OCA), the autosomal dominant disorder piebaldism to X-linked ocular albinism and multifactorial vitiligo. OCA connotes a group of disorders that result in hypopigmented skin due to decreased melanin production in melanocytes and loss of visual acuity. There are four non-syndromic forms, OCA1-4, which are classified based on the gene that is mutated (tyrosinase, OCA2, tyrosinase-related protein 1 and SLC45A2, respectively). Despite the fact that multiple genes account for the various forms of OCA, the phenotypes of all four forms result from disruption in the maturation and trafficking of the enzyme tyrosinase. OCA2 is the most prevalent autosomal recessive disorder among southern African blacks, affecting 1/3 900 individuals; while OCA3, although rare, is most prevalent in southern Africa. Another common pigmentation disorder in southern Africa is vitiligo, which affects 1 - 2% of people worldwide. Vitiligo is a complex, acquired disorder in which melanocytes are destroyed due to an autoimmune response. The aetiology underlying this disorder is poorly understood, although recent genetic association studies have begun to shed light on the contributing factors. Pigmentation disorders have significant psychosocial implications and co-morbidities, yet therapies are still lacking. Recent progress in our understanding of the pathobiology of both albinism and vitiligo may herald novel treatment strategies for these disorders.

The genomic architecture of African populations is poorly understood and there is considerable variation between ethno-linguistic groups. Genome-wide approaches have been extensively applied to search for genetic associations to complex traits in Europeans, but rarely in Africans. This is largely attributed to lower levels of funding, poor infrastructure and public health systems, and to the small pool of trained scientists. High levels of genetic variation and underlying population structure in Africans present significant challenges, but lower levels of linkage disequilibrium provide an opportunity for more effective localisation of causal variants. High throughput technologies, including dense genotyping arrays, genome sequencing and epigenome studies, together with plummeting costs, are making research more affordable, even for African scientists. Understanding the interactions between genome structure and environmental influences is essential to interpreting their contributions to the increase in infectious diseases and non-communicable diseases, exacerbated by adverse environments and lifestyle choices. The unique genome dynamics in African populations have an important role to play in understanding human health and susceptibility to disease., (Copyright © 2012. Published by Elsevier B.V.)

The populations of Africa harbour the greatest human genetic diversity following an evolutionary history tracing its beginnings on the continent to time before the emergence of Homo sapiens. Signatures of selection are detectable as responses to ancient environments and cultural practices, modulated by more recent events including infectious epidemics, migrations, admixture and, of course, chance. The age of high-throughput biology is not passing Africa by. African-based cohort studies and networks with an African footprint are ideal springboards for disease-related genetic and genomic studies. Initiatives like HapMap, the 1000 Genomes Project, MalariaGEN, the INDEPTH network and Human Heredity and Health in Africa are catalysts to exploring African genetic diversity and its role in the spectrum from health to disease. The challenges are abundant in dissecting biological questions in the light of linguistic, cultural, geographic and political boundaries and their respective roles in shaping health-related profiles. Will studies based on African populations lead to a new wave of discovery of genetic contributors to disease?

Skin pigmentation is a polygenic multifactorial trait determined by the cumulative effects of multiple genetic variants and environmental factors. Melanocortin-1 receptor (MC1R) is one of the genes involved in pigmentation, and has been implicated in the red hair and pale skin phenotype in human Caucasoid individuals. The present study was undertaken to identify variation at the MC1R locus in normally pigmented individuals in two African populations, sub-Saharan Negroids (22 unrelated individuals) and the San (17 unrelated individuals). The study showed considerable MC1R gene sequence variation with the detection of eight synonymous and three nonsynonymous mutations. This is the first report of nonsynonymous mutations in African individuals in the MC1R gene: L99I was found in a single San individual, S47I was detected in a single Negroid individual, and F196L was detected in five Negroid individuals (5/44; 0.11). The functional significance of these mutations is not known. Three of the eight synonymous mutations found, L106L (CTG --> CTA), F300F (TTC --> TTT), and T314T (ACA --> ACG) (also known as A942G), have been reported previously. T314T was the only variant that showed a significant difference between the Negroid and San populations (0.477 and 0.059, respectively; P = 1.6 x 10(-5)). Its low frequency in the San may be the result of random genetic drift in a population of small size, or selection. Several tests of neutrality of the MC1R coding region in these and other African populations were significant, suggesting that purifying selection (functional constraint) had occurred at this gene locus in Africans. This demonstrates that although some nonsynonymous MC1R mutations are tolerated in individuals with dark skin, this gene has likely played a significant role in the maintenance of dark pigmentation in Africans and normal pigment variation in non-African populations.

The worldwide pattern of single nucleotide polymorphism (SNP) variation is of great interest to human geneticists, population geneticists, and evolutionists, but remains incompletely understood. We studied the pattern in noncoding regions, because they are less affected by natural selection than are coding regions. Thus, it can reflect better the history of human evolution and can serve as a baseline for understanding the maintenance of SNPs in human populations. We sequenced 50 noncoding DNA segments each approximately 500 bp long in 10 Africans, 10 Europeans, and 10 Asians. An analysis of the data suggests that the sampling scheme is adequate for our purpose. The average nucleotide diversity (pi) for the 50 segments is only 0.061% +/- 0.010% among Asians and 0.064% +/- 0.011% among Europeans but almost twice as high (0.115% +/- 0.016%) among Africans. The African diversity estimate is even higher than that between Africans and Eurasians (0.096% +/- 0.012%). From available data for noncoding autosomal regions (total length = 47,038 bp) and X-linked regions (47,421 bp), we estimated the pi-values for autosomal regions to be 0.105, 0.070, 0.069, and 0.097% for Africans, Asians, Europeans, and between Africans and Eurasians, and the corresponding values for X-linked regions to be 0.088, 0.042, 0.053, and 0.082%. Thus, Africans differ from one another slightly more than from Eurasians, and the genetic diversity in Eurasians is largely a subset of that in Africans, supporting the out of Africa model of human evolution. Clearly, one must specify the geographic origins of the individuals sampled when studying pi or SNP density.

Human DNA variation is currently a subject of intense research because of its importance for studying human origins, evolution, and demographic history and for association studies of complex diseases. A approximately 10-kb region on chromosome 1, which contains only four small exons (each <155 bp), was sequenced for 61 humans (20 Africans, 20 Asians, and 21 Europeans) and for 1 chimpanzee, 1 gorilla, and 1 orangutan. We found 52 polymorphic sites among the 122 human sequences and 382 variant sites among the human, chimpanzee, gorilla, and orangutan sequences. For the introns sequenced (8,991 bp), the nucleotide diversity (pi) was 0.058% among all sequences, 0.076% among the African sequences, 0.047% among the Asian sequences, and 0.045% among the European sequences. A compilation of data revealed that autosomal regions have, on average, the highest pi value (0.091%), X-linked regions have a somewhat lower pi value (0.079%), and Y-linked regions have a very low pi value (0.008%). The lower polymorphism in the present region may be due to a lower mutation rate and/or selection in the gene containing these introns or in genes linked to this region. The present region and two other 10-kb noncoding regions all show a strong excess of low-frequency variants, indicating a relatively recent population expansion. This region has a low mutation rate, which was estimated to be 0.74 x 10 per nucleotide per year. An average estimate of approximately 12,600 for the long-term effective population size was obtained using various methods; the estimate was not far from the commonly used value of 10,000. Fu and Li's tests rejected the assumption of an equilibrium neutral Wright-Fisher population, largely owing to the high proportion of low-frequency variants. The age of the most recent common ancestor of the sequences in our sample was estimated to be more than 1 Myr. Allowing for some unrealistic assumptions in the model, this estimate would still suggest an age of more than 500,000 years, providing further evidence for a genetic history of humans much more ancient than the emergence of modern humans. The fact that many unique variants exist in Europe and Asia also suggests a fairly long genetic history outside of Africa and argues against a complete replacement of all indigenous populations in Europe and Asia by a small Africa stock. Moreover, the ancient genetic history of humans indicates no severe bottleneck during the evolution of humans in the last half million years; otherwise, much of the ancient genetic history would have been lost during a severe bottleneck. We suggest that both the "Out of Africa" and the multiregional models are too simple to explain the evolution of modern humans.

The allele frequency of a Taq 1 gamma-globin gene restriction fragment length polymorphism (RFLP) is reported in ten population groups. In four African populations the 3.0 kb RFLP is common (50/132 beta A chromosomes), whereas it is completely absent in six European/Asian populations (0/277 beta A chromosomes). This Taq 1 RFLP is thus a specific African population marker.