Dense sampling of ethnic groups within African countries reveals fine-scale genetic structure and extensive historical admixture.

Previous studies have highlighted how African genomes have been shaped by a complex series of historical events. Despite this, genome-wide data have only been obtained from a small proportion of present-day ethnolinguistic groups. By analyzing new autosomal genetic variation data of 1333 individuals from over 150 ethnic groups from Cameroon, Republic of the Congo, Ghana, Nigeria, and Sudan, we demonstrate a previously underappreciated fine-scale level of genetic structure within these countries, for example, correlating with historical polities in western Cameroon. By comparing genetic variation patterns among populations, we infer that many northern Cameroonian and Sudanese groups share genetic links with multiple geographically disparate populations, likely resulting from long-distance migrations. In Ghana and Nigeria, we infer signatures of intermixing dated to over 2000 years ago, corresponding to reports of environmental transformations possibly related to climate change. We also infer recent intermixing signals in multiple African populations, including Congolese, that likely relate to the expansions of Bantu language-speaking peoples.

A Rare Deep-Rooting D0 African Y-Chromosomal Haplogroup and Its Implications for the Expansion of Modern Humans Out of Africa.

Present-day humans outside Africa descend mainly from a single expansion out ∼50,000-70,000 years ago, but many details of this expansion remain unclear, including the history of the male-specific Y chromosome at this time. Here, we reinvestigate a rare deep-rooting African Y-chromosomal lineage by sequencing the whole genomes of three Nigerian men described in 2003 as carrying haplogroup DE* Y chromosomes, and analyzing them in the context of a calibrated worldwide Y-chromosomal phylogeny. We confirm that these three chromosomes do represent a deep-rooting DE lineage, branching close to the DE bifurcation, but place them on the D branch as an outgroup to all other known D chromosomes, and designate the new lineage D0. We consider three models for the expansion of Y lineages out of Africa ∼50,000-100,000 years ago, incorporating migration back to Africa where necessary to explain present-day Y-lineage distributions. Considering both the Y-chromosomal phylogenetic structure incorporating the D0 lineage, and published evidence for modern humans outside Africa, the most favored model involves an origin of the DE lineage within Africa with D0 and E remaining there, and migration out of the three lineages (C, D, and FT) that now form the vast majority of non-African Y chromosomes. The exit took place 50,300-81,000 years ago (latest date for FT lineage expansion outside Africa - earliest date for the D/D0 lineage split inside Africa), and most likely 50,300-59,400 years ago (considering Neanderthal admixture). This work resolves a long-running debate about Y-chromosomal out-of-Africa/back-to-Africa migrations, and provides insights into the out-of-Africa expansion more generally.

The Open Browlift.

The eyes and periorbital areas are critical components for the harmonious treatment of the aging face. The authors prefer the open browlift for rejuvenation of the forehead area. The open browlift is the most versatile, effective, and long-lasting method for the treatment of the forehead. The analysis of the forehead area, alternative treatments, variations in incisions, and key components of the surgical procedure are to be reviewed.

Little genetic differentiation as assessed by uniparental markers in the presence of substantial language variation in peoples of the Cross River region of Nigeria.

BACKGROUND: The Cross River region in Nigeria is an extremely diverse area linguistically with over 60 distinct languages still spoken today. It is also a region of great historical importance, being a) adjacent to the likely homeland from which Bantu-speaking people migrated across most of sub-Saharan Africa 3000-5000 years ago and b) the location of Calabar, one of the largest centres during the Atlantic slave trade. Over 1000 DNA samples from 24 clans representing speakers of the six most prominent languages in the region were collected and typed for Y-chromosome (SNPs and microsatellites) and mtDNA markers (Hypervariable Segment 1) in order to examine whether there has been substantial gene flow between groups speaking different languages in the region. In addition the Cross River region was analysed in the context of a larger geographical scale by comparison to bordering Igbo speaking groups as well as neighbouring Cameroon populations and more distant Ghanaian communities. RESULTS: The Cross River region was shown to be extremely homogenous for both Y-chromosome and mtDNA markers with language spoken having no noticeable effect on the genetic structure of the region, consistent with estimates of inter-language gene flow of 10% per generation based on sociological data. However the groups in the region could clearly be differentiated from others in Cameroon and Ghana (and to a lesser extent Igbo populations). Significant correlations between genetic distance and both geographic and linguistic distance were observed at this larger scale. CONCLUSIONS: Previous studies have found significant correlations between genetic variation and language in Africa over large geographic distances, often across language families. However the broad sampling strategies of these datasets have limited their utility for understanding the relationship within language families. This is the first study to show that at very fine geographic/linguistic scales language differences can be maintained in the presence of substantial gene flow over an extended period of time and demonstrates the value of dense sampling strategies and having DNA of known and detailed provenance, a practice that is generally rare when investigating sub-Saharan African demographic processes using genetic data.

Longevity of SMAS facial rejuvenation and support.

BACKGROUND: One of the most common questions asked by patients when they present for face lift surgery is "How long will this last?" The answer to this question is not clear from the literature. METHODS: The purpose of the study was to review a series of secondary face lifts performed between 2001 and 2008 with both the primary and secondary face lift performed by a single surgeon. There were 42 patients with full records available for review. Data were collected with regard to timing, surgical technique, complications, and reasons for early revision. RESULTS: The average age at the primary face lift was 50.2 years (range, 34.9 to 69.9 years) and the average age at the secondary face lift was 61.9 years (range, 43.6 to 77.2 years). The average length of time from the primary to secondary face lift was 11.9 years. Nine patients required a secondary face lift before it had been 5 years since the primary face lift (21.4 percent). Reasons for early secondary face lift (within 5 years of the primary) included loss of skin elasticity in five patients and increase in subplatysmal fat and skin neck folds due to weight gain, loss of elasticity secondary to protease inhibitors for human immunodeficiency virus infection, loss of skin elasticity due to corticosteroid use, and residual fullness of digastric and residual submental fat in one patient each. CONCLUSIONS: On average, a well-performed superficial musculoaponeurotic system flap face lift will last 12 years. Those patients who present with very poor skin elasticity secondary to sun damage may require an earlier secondary face lift.

Lower facial rejuvenation in the non-Caucasian face.

The goal would be similar to Caucasian patients in that all patients would like to have maximum improvement with minimal detectability of the surgical procedure. With regard to scars, the incisions must be no longer than necessary to accomplish the desired goal, and should be carefully placed so that color matches are ideal and there is no objectionable hair shift. In addition, the technique of making an incision for male patients should be made so that hairs will grow through the scars whenever possible. For non-Caucasian patients it is essential that attention be made to all of the known details and techniques, to avoid detection that surgery has been performed.

Analysis of the effects of subcutaneous musculoaponeurotic system facial support on the nasolabial crease.

The idea that traction on the subcutaneous musculoaponeurotic system (SMAS) deepens the nasolabial crease has been propagated through the plastic surgery literature. This notion is contrary to the senior author's experience. The purpose of the present study was to investigate the effects of mobilization of the SMAS on the nasolabial fold and crease. Intraoperative examination on the effect of traction on the SMAS was performed. Ten consecutive primary facelift patients underwent facelift procedures with SMAS support. Following mobilization of the SMAS, traction was placed on the SMAS without traction on the skin. In all cases, the nasolabial fold was effaced and the nasolabial crease did not deepen. The authors concluded that traction on the SMAS did not deepen the nasolabial crease.

Sex-Specific Genetic Data Support One of Two Alternative Versions of the Foundation of the Ruling Dynasty of the Nso' in Cameroon.

Sex-specific genetic data favor a specific variant of the oral history of the kingdom of Nso' (a Grassfields city-state in Cameroon) in which the royal family traces its descent from a founding ancestress who married into an autochthonous hunter-gatherer group. The distributions of Y chromosome and mitochondrial DNA variation in the Nso' in general and in the ruling dynasty in particular are consistent with specific Nso' marriage practices, suggesting strict conservation of the royal social class along agnatic lines. This study demonstrates the efficacy of using genetics to augment other sources of information (e.g., oral histories, archaeology, and linguistics) when seeking to recover the histories of African peoples.

Pushing the clock back 15 to 20 years with facial rejuvenation.

The goal of rejuvenation is to restore the good looks present 15 to 18 years before without having signs of surgical improvement. Patients should look like themselves at a younger age with specific improvement not present when younger, such as nose or neck contour.

Roundtable: discussion of "the difficult patient".

Eight renowned surgeons responded to questions centering on "difficult patients" in facial plastic surgery. Questions ranged from, "How do you manage a postoperative patient who looks 'OK,' if not great, to you but complains about the result?" to "What 'pearl of advice' would you offer a novice surgeon on how to best avoid difficult situations with their patients?" The surgeons taking part in the discussion, from different practices in different parts of the country, provided a lively discussion based on their years of experience.

Correcting deformities of the aged earlobe.

An earlobe that appears aged or malpositioned can sabotage the results of a well performed face lift. The most frequently noted sign of a naturally aged earlobe is increased length. Improper planning of face lift incisions may also result in disfigurement of the ear. The author suggests simple excisional techniques to correct the aged earlobe, as well as methods to avoid subsequent earlobe distortion when performing a face lift.

The T allele of a single-nucleotide polymorphism 13.9 kb upstream of the lactase gene (LCT) (C-13.9kbT) does not predict or cause the lactase-persistence phenotype in Africans.

The ability to digest the milk sugar lactose as an adult (lactase persistence) is a variable genetic trait in human populations. The lactase-persistence phenotype is found at low frequencies in the majority of populations in sub-Saharan Africa that have been tested, but, in some populations, particularly pastoral groups, it is significantly more frequent. Recently, a CT polymorphism located 13.9 kb upstream of exon 1 of the lactase gene (LCT) was shown in a Finnish population to be closely associated with the lactase-persistence phenotype (Enattah et al. 2002). We typed this polymorphism in 1,671 individuals from 20 distinct cultural groups in seven African countries. It was possible to match seven of the groups tested with groups from the literature for whom phenotypic information is available. In five of these groups, the published frequencies of lactase persistence are >/=25%. We found the T allele to be so rare that it cannot explain the frequency of the lactase-persistence phenotype throughout Africa. By use of a statistical procedure to take phenotyping and sampling errors into account, the T-allele frequency was shown to be significantly different from that predicted in five of the African groups. Only the Fulbe and Hausa from Cameroon possessed the T allele at a level consistent with phenotypic observations (as well as an Irish sample used for comparison). We conclude that the C-13.9kbT polymorphism is not a predictor of lactase persistence in sub-Saharan Africans. We also present Y-chromosome data that are consistent with previously reported evidence for a back-migration event into Cameroon, and we comment on the implications for the introgression of the -13.9kb*T allele.

Rare deep-rooting Y chromosome lineages in humans: lessons for phylogeography.

There has been considerable debate on the geographic origin of the human Y chromosome Alu polymorphism (YAP). Here we report a new, very rare deep-rooting haplogroup within the YAP clade, together with data on other deep-rooting YAP clades. The new haplogroup, found so far in only five Nigerians, is the least-derived YAP haplogroup according to currently known binary markers. However, because the interior branching order of the Y chromosome genealogical tree remains unknown, it is impossible to impute the origin of the YAP clade with certainty. We discuss the problems presented by rare deep-rooting lineages for Y chromosome phylogeography.

Male face lift.

The author describes how to use the deep layer support technique for male face lift to achieve natural-looking results and virtually undetectable scars. He discusses incisions and neck contouring in detail and provides pointers on eliminating crow's-feet. (Aesthetic Surg J 2002;22:385-396.).