Genetic studies in French Guiana populations: Synthesis

International audienceTwelve blood group and protein systems from a total of 819 individuals from six tribal groups (Apalaí-Wayana, Emerillon, Kaliña, Palikur Wayampi, and Wayana) living in French Guiana and Brazil were compared with each other and integrated with previous results from 17 other South Amerindian populations studied for the same genetic markers. Using correspondence analysis, map methodologies, and maximum linkage cluster analysis developed with the UPGMA method, we attempted to establish the genetic position of these tribes among South American Indians. Peripheral positions for the Emerillon and the Palikur were observed. Ethnohistorical data in French Guiana suggest that a strong founder effect for the former and endogamy for the latter could have generated the genetic differentiation of these two ethnic groups. However, when considered in a wider context, all French Guiana Natives cluster together in an intermediate position as compared with 17 other Amerindian groups studied for the comparison

Population genetic dynamics in the French Guiana region

International audienceThree sets of genetic markers (blood group plus protein polymorphisms, mitochondrial DNA and Y-chromosome) were compared in four French Guiana and one Brazilian Amerindian populations. Spearman's rank correlation coefficient between five gene diversity statistics and historical or present-day population sizes showed significant values, indicating loss of diversity due to population bottlenecks. The three sets of markers furnished distinct admixture estimates, and the blood group plus protein polymorphisms could have overestimated the European contribution to their gene pool. Correspondence analysis distinguished the coastal from the interior populations, possibly reflecting past migration events

French Guiana Amerindian demographic history as revealed by autosomal and Y-chromosome STRs.

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Uniparental (mtDNA, Y-chromosome) Polymorphisms in French Guiana and Two Related Populations - Implications for the Region's Colonization

International audienceBlood samples collected in four Amerindian French Guiana populations (Palikur, Emerillon, Wayampi and Kali'na) in the early 1980s were screened for selected mtDNA and Y-chromosome length polymorphisms, and sequenced for the mtDNA hypervariable segment I (HVS-I). In addition, two other Amerindian populations (Apalaí and Matsiguenga) were examined for the same markers to establish the genetic relationships in the area. Strong dissimilarities were observed in the distribution of the founding Amerindian haplogroups, and significant p-values were obtained from F(ST) genetic distances. Interpopulation similarities occurred mainly due to geography. The Palikur did not show obvious genetic similarity to the Matsiguenga, who speak the same language and live in a region from where they could have migrated to French Guiana. The African-origin admixture observed in the Kali'na probably derives from historical contacts they had with the Bushinengue (Noir Marron), a group of escaped slaves who now lead independent lives in a nearby region. This analysis has identified significant clues about the Amerindian peopling of the North-East Amazonian region

The imprint of the Slave Trade in an African American population: mitochondrial DNA, Y chromosome and HTLV-1 analysis in the Noir Marron of French Guiana

<p>Abstract</p> <p>Background</p> <p>Retracing the genetic histories of the descendant populations of the Slave Trade (16^th-19^thcenturies) is particularly challenging due to the diversity of African ethnic groups involved and the different hybridisation processes with Europeans and Amerindians, which have blurred their original genetic inheritances. The Noir Marron in French Guiana are the direct descendants of maroons who escaped from Dutch plantations in the current day Surinam. They represent an original ethnic group with a highly blended culture. Uniparental markers (mtDNA and NRY) coupled with HTLV-1 sequences (<it>env </it>and LTR) were studied to establish the genetic relationships linking them to African American and African populations.</p> <p>Results</p> <p>All genetic systems presented a high conservation of the African gene pool (African ancestry: mtDNA = 99.3%; NRY = 97.6%; HTLV-1 e<it>nv </it>= 20/23; HTLV-1 LTR = 6/8). Neither founder effect nor genetic drift was detected and the genetic diversity is within a range commonly observed in Africa. Higher genetic similarities were observed with the populations inhabiting the Bight of Benin (from Ivory Coast to Benin). Other ancestries were identified but they presented an interesting sex-bias. Whilst male origins spread throughout the north of the bight (from Benin to Senegal), female origins were spread throughout the south (from the Ivory Coast to Angola).</p> <p>Conclusions</p> <p>The Noir Marron are unique in having conserved their African genetic ancestry, despite major cultural exchanges with Amerindians and Europeans through inhabiting the same region for four centuries. Their maroon identity and the important number of slaves deported in this region have maintained the original African diversity. All these characteristics permit to identify a major origin located in the former region of the Gold Coast and the Bight of Benin; regions highly impacted by slavery, from which goes a sex-biased longitudinal gradient of ancestry.</p

Âge au premier mariage, contraception et mortalité infantile : influence sur l'évolution de la fécondité d'une population berbère du Haut Atlas marocain (vallée d'Anougal)

L’évolution récente de la fécondité et de ses principaux déterminants dans une population berbère traditionnelle du Haut-Atlas occidental marocain a été caractérisée par une série de trois enquêtes rétrospectives complémentaires. Les résultats obtenus montrent un début de transition démographique. La baisse de la fécondité qui a touché toutes les classes d’âges est à mettre en relation avec un accroissement de l’âge au mariage et une régression de la mortalité infantile. La contraception moderne, quant à elle, ne semble pas avoir encore l’effet escompté.The recent fertility trends within a traditional Berber population of the Western High Atlas mountains (Anougal valley) and the main factors responsible for these trends have been studied during three retrospective and complementary inquiries. Results showed that a demographic transition has started within the population. The decrease in fertility observed in all age classes is related to the increase of age at first marriage and the decrease in infant mortality. The modern contraceptive methods don’t seem to be responsible for the observed  transition

Reconstructing Native American Population History

The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. We show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call “First American”. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan-speakers on both sides of the Panama Isthmus, who have ancestry from both North and South America

Dynastes satanas Moser : nouvelle découverte et description des pièces génitales du mâle [Col. Dynastidae]

Larrouy Georges. Dynastes satanas Moser : nouvelle découverte et description des pièces génitales du mâle [Col. Dynastidae]. In: Bulletin de la Société entomologique de France, volume 86 (9-10), Novembre-décembre 1981. pp. 244-246

J. Ruffié, De la Biologie à la culture

Larrouy Georges. J. Ruffié, De la Biologie à la culture. In: L'Homme, 1977, tome 17 n°2-3. pp. 192-194