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1.
J Biosoc Sci ; 55(1): 174-189, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34907866

RESUMEN

An analysis of the distribution of surnames through time and space allows us to understand the structure of human groups, their exchanges or even their possible isolation. The French population has already been studied through surnames and it has been shown that the Sud-Provence-Alpes-Côte d'Azur region differed from the rest of France in both the 20th and 21st centuries (Mourrieras et al., ; Scapoli et al., ). The objective of this study was to understand the population evolution and particularities of the Sud-Provence-Alpes-Côte d'Azur region through an analysis of the distribution of surnames over an earlier period: the 19th century. For this work, 806,069 birth records from 521 communes between 1810 and 1890 were recorded and a total of 23,340 surnames were collected. The estimation of various isonymic parameters has allowed a description of this corpus never exploited before. In order to appreciate the population evolution, the data set was divided into three periods of 25 years. The canton was the geographical unit of this study, and similarities and differences between each of them were evaluated using Lasker distances, which allow the construction of dendrograms. A positive and significant correlation (p<0.0001) was found between Lasker distances and geographical distances using the Mantel test. The lowest inbreeding estimates were found in the Durance Valley. Migration, estimated from the v-index of Karlin and McGregor (), showed higher values in the south-western quarter of the region. The decrease in Rst values across the three periods is consistent with a homogenization of the patronymic between the cantons. This three-period approach showed a population evolution influenced by linguistic, cultural, historical and migratory phenomena since the Middle Ages, disrupted by the socioeconomic changes of the 19th century.


Asunto(s)
Nombres , Población Rural , Humanos , Certificado de Nacimiento , Población Blanca , Geografía , Genética de Población
2.
Front Zool ; 10(1): 22, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23634901

RESUMEN

INTRODUCTION: Hybridization is a common phenomenon in fish and is considered to be a major source of diversification. Deciphering the remoulding of genomic regions and phenotypes in zones where hybrid specimens occur is of particular interest to elucidate the emergence of evolutionary novelties. This approach is particularly challenging because the first step of hybridization seems to be the most important stage in the emergence of hybrid lineages. However, the signal can be significantly altered after only a few generations. RESULTS: We studied 41 microsatellites and partial cytochrome b gene sequences in 970 specimens belonging to two fish species (Chondrostoma nasus and Parachondrostoma toxostoma) in allopatric/parapatric zones, hybrids between them in a natural sympatric zone: the Ardèche basin. We showed that the genomic architecture in hybrids presented pattern heterogeneity of selection for the different loci. Indeed, the upstream part of the river (Rosières and Labeaume) presented an overdominant fitness of heterozygotes (12.20%) corresponding to a genomic compatibility, and underselection was observed for 4.88%-7.32% of the loci tested indicating a genomic incompatibility. Moreover the upstream station (Rosières) presented a positive selection of invasive C. nasus homozygotes (17.07% to 21.95%) indicating that hybridization may increase the fitness of admixed individuals.We showed that hybrid morphology (body shape based on 21 landmarks) correlated with genomic dilution indicating a species fingerprint. However, we demonstrated that the hybrid morphology was not a linear modification between the two parental species but a trade-off between several correlated traits. CONCLUSIONS: Hybrid specimens present a mosaic of genomic combination, showing regions with genomic compatibility and others with genomic incompatibility between the two species. Positive selection (invasive advantage ranging from 9.76% to 21.95% of the loci) was evidenced in the upstream part of the Ardèche indicating that environmental selection makes a substantial contribution. Although the presence of a dam is known to impose heterogeneous hybrid zones between these two species, we demonstrated in this study that a natural environment can also generate a hybrid zone with a large number (and diversity) of hybrids. The combination of the two genomes in the hybrids results in complex ontogenetic trajectories (with different morphological traits evolving at different rates) that correspond to novel developmental pathways.

3.
Front Med (Lausanne) ; 10: 1265964, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143446

RESUMEN

Introduction: The lack of well-preserved material upon which to base the paleo-microbiological detection of Plasmodium parasites has prevented extensive documentation of past outbreaks of malaria in Europe. By trapping intact erythrocytes at the time of death, dental pulp has been shown to be a suitable tissue for documenting ancient intraerythrocytic pathogens such as Plasmodium parasites. Methods: Total DNA and proteins extracted from 23 dental pulp specimens collected from individuals exhumed from the 9th to 13th century archaeological site in Mariana, Corsica, were analyzed using open-mind paleo-auto-immunohistochemistry and direct metagenomics, Plasmodium-targeting immunochromatography assays. All experiments incorporated appropriate negative controls. Results: Paleo-auto-immunohistochemistry revealed the presence of parasites Plasmodium spp. in the dental pulp of nine teeth. A further immunochromatography assay identified the presence of at least one Plasmodium antigen in nine individuals. The nine teeth, for which the PfHRP-2 antigen specific of P. falciparum was detected, were also positive using paleo-autoimmunohistochemistry and metagenomics. Conclusion: Dental pulp erythrocytes proved to be suitable for the direct paleomicrobiology documentation of malaria in nine individuals buried in medieval Corsica, in agreement with historical data. This provides additional information on the millennial dynamics of Plasmodium spp. in the Mediterranean basin.

4.
iScience ; 26(5): 106787, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37250315

RESUMEN

Ancient DNA preserved in the dental pulp offers the opportunity to characterize the genome of some of the deadliest pathogens in human history. However, while DNA capture technologies help, focus sequencing efforts, and therefore, reduce experimental costs, the recovery of ancient pathogen DNA remains challenging. Here, we tracked the kinetics of ancient Yersinia pestis DNA release in solution during a pre-digestion of the dental pulp. We found that most of the ancient Y. pestis DNA is released within 60 min at 37°C in our experimental conditions. We recommend a simple pre-digestion as an economical procedure to obtain extracts enriched in ancient pathogen DNA, as longer digestion times release other types of templates, including host DNA. Combining this procedure with DNA capture, we characterized the genome sequences of 12 ancient Y. pestis bacteria from France dating to the second pandemic outbreaks of the 17th and 18th centuries Common Era.

5.
Genes (Basel) ; 13(10)2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36292737

RESUMEN

After causing mass disasters that claimed the lives of tens of thousands of soldiers from countries around the world, the two Great Wars left some of them lost and missing. In France, these corpses reside in a legal vagueness where they belong neither to forensic anthropology nor archeology. Nevertheless, the process of identification and determining the cause of death requires the use of modern forensic anthropology by applying biological profiling and DNA analysis. New genomic methods also provide insight into the health statuses of these military populations, providing new perspectives on these periods of humanitarian crisis.


Asunto(s)
Restos Mortales , Personal Militar , Humanos , Antropología Forense/métodos , Cadáver , ADN
6.
Bioinformatics ; 26(3): 403-4, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20007741

RESUMEN

SUMMARY: QDD is an open access program providing a user-friendly tool for microsatellite detection and primer design from large sets of DNA sequences. The program is designed to deal with all steps of treatment of raw sequences obtained from pyrosequencing of enriched DNA libraries, but it is also applicable to data obtained through other sequencing methods, using FASTA files as input. The following tasks are completed by QDD: tag sorting, adapter/vector removal, elimination of redundant sequences, detection of possible genomic multicopies (duplicated loci or transposable elements), stringent selection of target microsatellites and customizable primer design. It can treat up to one million sequences of a few hundred base pairs in the tag-sorting step, and up to 50,000 sequences in a single input file for the steps involving estimation of sequence similarity. AVAILABILITY: QDD is freely available under the GPL licence for Windows and Linux from the following web site: http://www.univ-provence.fr/gsite/Local/egee/dir/meglecz/QDD.html. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Biología Computacional/métodos , Cartilla de ADN/química , Repeticiones de Microsatélite , Análisis de Secuencia de ADN/métodos , Programas Informáticos , Secuencia de Bases , Bases de Datos Genéticas
7.
PLoS One ; 16(7): e0254175, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34320013

RESUMEN

Blood group systems were the first phenotypic markers used in anthropology to decipher the origin of populations, their migratory movements, and their admixture. The recent emergence of new technologies based on the decoding of nucleic acids from an individual's entire genome has relegated them to their primary application, blood transfusion. Thus, despite the finer mapping of the modern human genome in relation to Neanderthal and Denisova populations, little is known about red cell blood groups in these archaic populations. Here we analyze the available high-quality sequences of three Neanderthals and one Denisovan individuals for 7 blood group systems that are used today in transfusion (ABO including H/Se, Rh (Rhesus), Kell, Duffy, Kidd, MNS, Diego). We show that Neanderthal and Denisova were polymorphic for ABO and shared blood group alleles recurrent in modern Sub-Saharan populations. Furthermore, we found ABO-related alleles currently preventing from viral gut infection and Neanderthal RHD and RHCE alleles nowadays associated with a high risk of hemolytic disease of the fetus and newborn. Such a common blood group pattern across time and space is coherent with a Neanderthal population of low genetic diversity exposed to low reproductive success and with their inevitable demise. Lastly, we connect a Neanderthal RHD allele to two present-day Aboriginal Australian and Papuan, suggesting that a segment of archaic genome was introgressed in this gene in non-Eurasian populations. While contributing to both the origin and late evolutionary history of Neanderthal and Denisova, our results further illustrate that blood group systems are a relevant piece of the puzzle helping to decipher it.


Asunto(s)
Antígenos de Grupos Sanguíneos/genética , Hominidae/genética , Hombre de Neandertal/genética , Alelos , Animales , Fósiles , Variación Genética , Genotipo , Mutación INDEL , Fenotipo , Polimorfismo Genético
8.
iScience ; 24(4): 102383, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33981971

RESUMEN

The 17th century plague epidemic had a particularly strong demographic toll in Southern Europe, especially Italy, where it caused long-lasting economical damage. Whether this resulted from ineffective sanitation measures or more pathogenic Yersinia pestis strains remains unknown. DNA screening of 26 skeletons from the 1629-1630 plague cemetery of Lariey (French Alps) identified two teeth rich in plague genetic material. Further sequencing revealed two Y. pestis genomes phylogenetically closest to those from the 1636 outbreak of San Procolo a Naturno, Italy. They both belonged to a cluster extending from the Alps to Northern Germany that probably propagated during the Thirty Years war. Sequence variation did not support faster evolutionary rates in the Italian genomes and revealed only rare private non-synonymous mutations not affecting virulence genes. This, and the more heterogeneous spatial diffusion of the epidemic outside Italy, suggests environmental or social rather than biological causes for the severe Italian epidemic trajectory.

9.
Brain Sci ; 11(11)2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34827404

RESUMEN

While recent advances in genetics make it possible to follow the genetic exchanges between populations and their phenotypic consequences, the impact of the genetic exchanges on the sensory perception of populations has yet to be explored. From this perspective, the present study investigated the consequences of African gene flow on odor perception in a Malagasy population with a predominantly East Asian genetic background. To this end, we combined psychophysical tests with genotype data of 235 individuals who were asked to smell the odorant molecule beta-ionone (ßI). Results showed that in this population the ancestry of the OR5A1 gene significantly influences the ability to detect ßI. At the individual level, African ancestry significantly protects against specific anosmia/hyposmia due to the higher frequency of the functional gene (OR ratios = 14, CI: 1.8-110, p-value = 0.012). At the population level, African introgression decreased the prevalence of specific anosmia/hyposmia to this odorous compound. Taken together, these findings validate the conjecture that in addition to cultural exchanges, genetic transfer may also influence the sensory perception of the population in contact.

10.
Sci Adv ; 7(6)2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33547071

RESUMEN

To characterize the genetic basis of facial features in Latin Americans, we performed a genome-wide association study (GWAS) of more than 6000 individuals using 59 landmark-based measurements from two-dimensional profile photographs and ~9,000,000 genotyped or imputed single-nucleotide polymorphisms. We detected significant association of 32 traits with at least 1 (and up to 6) of 32 different genomic regions, more than doubling the number of robustly associated face morphology loci reported until now (from 11 to 23). These GWAS hits are strongly enriched in regulatory sequences active specifically during craniofacial development. The associated region in 1p12 includes a tract of archaic adaptive introgression, with a Denisovan haplotype common in Native Americans affecting particularly lip thickness. Among the nine previously unidentified face morphology loci we identified is the VPS13B gene region, and we show that variants in this region also affect midfacial morphology in mice.


Asunto(s)
Cara , Polimorfismo de Nucleótido Simple , Proteínas de Transporte Vesicular , Animales , Cara/anatomía & histología , Estudio de Asociación del Genoma Completo , Genotipo , Hispánicos o Latinos/genética , Humanos , Ratones , Fenotipo , Proteínas de Transporte Vesicular/genética
11.
BMC Genomics ; 11: 560, 2010 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-20939885

RESUMEN

BACKGROUND: Microsatellites are markers of choice in population genetics and genomics, as they provide useful insight into patterns and processes as diverse as genome evolutionary dynamics and demographic processes. The acquisition of microsatellites through multiplex-enriched libraries and 454 GS-FLX Titanium pyrosequencing is a promising new tool for the isolation of new markers in unknown genomes. This approach can also be used to evaluate the extent to which microsatellite-enriched libraries are representative of the genome from which they were isolated. In this study, we deciphered potential discrepancies in microsatellite content recovery for two reference genomes (Apis mellifera and Danio rerio), selected on the basis of their extreme heterogeneity in terms of the proportions and distributions of microsatellites on chromosomes. RESULTS: The A. mellifera genome, in particular, was found to be highly heterogeneous, due to extremely high rates of recombination, with hotspots, but the only bias consistently introduced into pyrosequenced multiplex-enriched libraries concerned sequence length, with the overrepresentation of sequences 160 to 320 bp in length. Other deviations from expected proportions or distributions of motifs on chromosomes were observed, but the significance and intensity of these deviations was mostly limited. Furthermore, no consistent adverse competition between multiplexed probes was observed during the motif enrichment phase. CONCLUSIONS: This approach therefore appears to be a promising strategy for improving the development of microsatellites, as it introduces no major bias in terms of the proportions and distribution of microsatellites.


Asunto(s)
Abejas/genética , Genoma/genética , Repeticiones de Microsatélite/genética , Análisis de Secuencia de ADN/métodos , Temperatura , Titanio/química , Pez Cebra/genética , Animales , Secuencia de Bases , Sesgo , Cromosomas/genética , Sondas de ADN/metabolismo , Biblioteca de Genes , Sitios Genéticos/genética , Modelos Genéticos
12.
Forensic Sci Int ; 316: 110484, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32942184

RESUMEN

The study of human remains from the first and the second World War is important for enhancing our understanding of that historical period. Despite the fact that the period has been well-documented previously, gaps remain, particularly as a result of the destruction of archives. In fact, for just WWI, more than 700,000 soldiers from both sides remain missing. Scientific and political collaborations established in hopes of recovering and identifying soldiers will allow many families understand "what happened" to their loved ones and facilitate the return of the soldiers their homes. In this paper, the recovery of the human remains of French soldiers WWI and WWII will be described through the lens of the legislation in place governing the retrieval and identification of the remains, protocols established for recovery, excavation and analysis, and the dissemination data. These features will be illustrated using three case studies that involve French soldiers who died during WWI. Research of this type is the result of true interdisciplinary and sometimes international, depending on the context, collaboration. The public and academic the dissemination of these archaeological discoveries, both to academics and the public, is crucial and a type of remembrance.


Asunto(s)
Restos Mortales , Personal Militar , Arqueología , Huesos , Dermatoglifia del ADN , Ciencias Forenses , Francia , Historia del Siglo XX , Humanos , Masculino , Primera Guerra Mundial , Segunda Guerra Mundial
13.
Front Zool ; 6: 26, 2009 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-19860907

RESUMEN

BACKGROUND: The invasive Chondrostoma nasus nasus has colonized part of the distribution area of the protected endemic species Chondrostoma toxostoma toxostoma. This hybrid zone is a complex system where multiple effects such as inter-species competition, bi-directional introgression, strong environmental pressure and so on are combined. Why do sympatric Chondrostoma fish present a unidirectional change in body shape? Is this the result of inter-species interactions and/or a response to environmental effects or the result of trade-offs? Studies focusing on the understanding of a trade-off between multiple parameters are still rare. Although this has previously been done for Cichlid species flock and for Darwin finches, where mouth or beak morphology were coupled to diet and genetic identification, no similar studies have been done for a fish hybrid zone in a river. We tested the correlation between morphology (body and mouth morphology), diet (stable carbon and nitrogen isotopes) and genomic combinations in different allopatric and sympatric populations for a global data set of 1330 specimens. To separate the species interaction effect from the environmental effect in sympatry, we distinguished two data sets: the first one was obtained from a highly regulated part of the river and the second was obtained from specimens coming from the less regulated part. RESULTS: The distribution of the hybrid combinations was different in the two part of the sympatric zone, whereas all the specimens presented similar overall changes in body shape and in mouth morphology. Sympatric specimens were also characterized by a larger diet behavior variance than reference populations, characteristic of an opportunistic diet. No correlation was established between the body shape (or mouth deformation) and the stable isotope signature. CONCLUSION: The Durance River is an untamed Mediterranean river despite the presence of numerous dams that split the river from upstream to downstream. The sympatric effect on morphology and the large diet behavior range can be explained by a tendency toward an opportunistic behavior of the sympatric specimens. Indeed, the similar response of the two species and their hybrids implied an adaptation that could be defined as an alternative trade-off that underline the importance of epigenetics mechanisms for potential success in a novel environment.

14.
Eur J Hum Genet ; 27(1): 125-132, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30143806

RESUMEN

Red cell polymorphisms can provide evidence of human migration and adaptation patterns. In Eurasia, the distribution of Diego blood group system polymorphisms remains unaddressed. To shed light on the dispersal of the Dia antigen, we performed analyses of correlations between the frequencies of DI*01 allele, C2-M217 and C2-M401 Y-chromosome haplotypes ascribed as being of Mongolian-origin and language affiliations, in 75 Eurasian populations including DI*01 frequency data from the HGDP-CEPH panel. We revealed that DI*01 reaches its highest frequency in Mongolia, Turkmenistan and Kyrgyzstan, expanding southward and westward across Asia with Altaic-speaking nomadic carriers of C2-M217, and even more precisely C2-M401, from their homeland presumably in Mongolia, between the third century BCE and the thirteenth century CE. The present study has highlighted the gene-culture co-migration with the demographic movements that occurred during the past two millennia in Central and East Asia. Additionally, this work contributes to a better understanding of the distribution of immunogenic erythrocyte polymorphisms with a view to improve transfusion safety.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/genética , Pueblo Asiatico/genética , Migración Humana , Polimorfismo Genético , Asia , Cromosomas Humanos Y/genética , Femenino , Haplotipos , Humanos , Masculino
15.
Forensic Sci Int ; 296: 145-152, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30712776

RESUMEN

This case study reports the anthropological analysis of bones remains discovered on Riou Island (Marseille, France) and the story of two World War II fighter pilots. The discovery of bones on "The Fountain of the Greeks" square on Riou Island occurred in the 1960's and a first anthropological study described a 35-year-old man, about 1.77 m tall, buried since an estimated period between the 13th and 16th centuries. The case was "closed" and the bones were considered as isolated archaeological remains. Few years later, near the coasts of Riou Island, parts of two planes were discovered. One was from of a German Messerschmitt Bf 109 F-4 of the Luftwaffe piloted by Prince Alexis fürst zu Bentheim und Steinfurt, and the other from a French P-38 Lightning F-5 B piloted by Antoine de Saint-Exupery. Therefore, the identification of the skeletal remains mentioned above was then thought to be perhaps one of the two World War II pilots. In this particular context we performed forensic and molecular biology analyses to resolve this identification.


Asunto(s)
Huesos/química , Huesos/patología , Dermatoglifia del ADN , Antropología Forense , Pilotos , Determinación de la Edad por el Esqueleto/métodos , Determinación de la Edad por los Dientes/métodos , ADN/aislamiento & purificación , ADN Mitocondrial/genética , Francia , Historia del Siglo XX , Humanos , Masculino , Repeticiones de Microsatélite , Personal Militar , Reacción en Cadena de la Polimerasa , Datación Radiométrica , Determinación del Sexo por el Esqueleto/métodos , Segunda Guerra Mundial
16.
Eur J Hum Genet ; 26(8): 1222-1226, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29706642

RESUMEN

Post-marital residence of spouses is one of the architects of population genetic structure. In the present study, we tested how the place of residence of males and females in Ngazidja, Comoros Islands, has unequally channeled, by dispersal among villages, the male and female genetic diversity. Using sequences of the hypervariable segment I of the mitochondrial DNA (mtDNA HVS-I) and six Y-chromosome microsatellites (Y-STRs), we measured the genetic variation and male-to-female effective number of migrants ratios based on FST values and revealed a genetic structure mostly driven by male gene flow across villages. This genetic feature illustrates the uxori-matrilocality inherited from the Bantu expansion, though one exception exists in Bandamadji whose historically documented military status implied patrilocality in this locality.


Asunto(s)
Cromosomas Humanos Y/genética , Flujo Génico , Impresión Genómica , Migración Humana , Población/genética , ADN Mitocondrial/genética , Femenino , Humanos , Islas del Oceano Índico , Masculino , Repeticiones de Microsatélite , Polimorfismo Genético
18.
PLoS One ; 10(11): e0142592, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26561027

RESUMEN

Understanding the impact of non-native species on native species is a major challenge in molecular ecology, particularly for genetically compatible fish species. Invasions are generally difficult to study because their effects may be confused with those of environmental or human disturbances. Colonized ecosystems are differently impacted by human activities, resulting in diverse responses and interactions between native and non-native species. We studied the dynamics between two Cyprinids species (invasive Chondrostoma nasus and endemic Parachondrostoma toxostoma) and their hybrids in 16 populations (from allopatric to sympatric situations and from little to highly fragmented areas) corresponding to 2,256 specimens. Each specimen was assigned to a particular species or to a hybrid pool using molecular identification (cytochrome b and 41 microsatellites). We carried out an ecomorphological analysis based on size, age, body shape, and diet (gut vacuity and molecular fecal contents). Our results contradicted our initial assumptions on the pattern of invasion and the rate of introgression. There was no sign of underperformance for the endemic species in areas where hybridisation occurred. In the unfragmented zone, the introduced species was found mostly downstream, with body shapes similar to those in allopatric populations while both species were found to be more insectivorous than the reference populations. However, high level of hybridisation was detected, suggesting interactions between the two species during spawning and/or the existence of hybrid swarm. In the disturbed zone, introgression was less frequent and slender body shape was associated with diatomivorous behaviour, smaller size (juvenile characteristics) and greater gut vacuity. Results suggested that habitat degradation induced similar ecomorphological trait changes in the two species and their hybrids (i.e. a transition towards a pedomorphic state) where the invasive species is more affected than the native species. Therefore, this study reveals a diversity of relationships between two genetically compatible species and emphasizes constraints on the invasion process in disturbed areas.


Asunto(s)
Cyprinidae/fisiología , Ecosistema , Especies Introducidas , Ríos , Algoritmos , Animales , Tamaño Corporal , Conservación de los Recursos Naturales , Citocromos b/genética , Dieta , Conducta Alimentaria , Francia , Geografía , Hibridación Genética , Repeticiones de Microsatélite/genética , Especificidad de la Especie , Temperatura
19.
PLoS One ; 7(3): e34423, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22479629

RESUMEN

Investigating processes and timing of differentiation of organisms is critical in the understanding of the evolutionary mechanisms involved in microevolution, speciation, and macroevolution that generated the extant biodiversity. From this perspective, the Telestes genus is of special interest: the Telestes species have a wide distribution range across Europe (from the Danubian district to Mediterranean districts) and have not been prone to translocation. Molecular data (mtDNA: 1,232 bp including the entire Cyt b gene; nuclear genome: 11 microsatellites) were gathered from 34 populations of the Telestes genus, almost encompassing the entire geographic range. Using several phylogenetic and molecular dating methods interpreted in conjunction with paleoclimatic and geomorphologic evidence, we investigated the processes and timing of differentiation of the Telestes lineages. The observed genetic structure and diversity were largely congruent between mtDNA and microsatellites. The Messinian Salinity Crisis (Late Miocene) seems to have played a major role in the speciation processes of the genus. Focusing on T. souffia, a species occurring in the Danube and Rhone drainages, we were able to point out several specific events from the Pleistocene to the Holocene that have likely driven the differentiation and the historical demography of this taxon. This study provides support for an evolutionary history of dispersal and vicariance with unprecedented resolution for any freshwater fish in this region.


Asunto(s)
Cyprinidae/genética , Evolución Molecular , Animales , Citocromos b/genética , ADN Mitocondrial/genética , Europa (Continente) , Variación Genética , Genética de Población , Repeticiones de Microsatélite , Filogenia
20.
Parasit Vectors ; 5: 200, 2012 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-22967821

RESUMEN

BACKGROUND: The composition of parasite communities in two cyprinid species in southern France - native and threatened Parachondrostoma toxostoma and introduced Chondrostoma nasus - was investigated. In sympatry, these two species form two hybrid zones in the Durance and Ardeche Rivers. Due to their different feeding preference and habitat positions in allopatry, we supposed a difference in parasite communities between fish species. We expected more similar parasite communities in sympatric zones associated with habitat overlap (facilitating the transmission of ectoparasites) and similar feeding (more generalist behaviour when compared to allopatry, facilitating the transmission of endoparasites) in both fish species. Finally, we investigated whether P. toxostoma x C. nasus hybrids are less parasitized then parental species. METHODS: One allopatric population of each fish species plus two sympatric zones were sampled. Fish were identified using cytochrome b gene and 41 microsatellites loci and examined for all metazoan parasites. RESULTS: A high Monogenea abundance was found in both allopatric and sympatric populations of C. nasus. Trematoda was the dominant group in parasite communities of P. toxostoma from the allopatric population. In contrast, the populations of P. toxostoma in sympatric zones were parasitized by Dactylogyrus species found in C. nasus populations, but their abundance in endemic species was low. Consequently, the similarity based on parasite presence/absence between the sympatric populations of P. toxostoma and C. nasus was high. Sympatric populations of P. toxostoma were more similar than allopatric and sympatric populations of this species. No difference in ectoparasite infection was found between P. toxostoma and hybrids, whilst C. nasus was more parasitized by Monogenea. CONCLUSIONS: The differences in endoparasites between P. toxostoma and C. nasus in allopatry are probably linked to different feeding or habitat conditions, but host-parasite evolutionary associations also play an important role in determining the presence of Chondrostoma-specific monogeneans. Our findings suggest that Dactylogyrus expanded with the source host C. nasus into introduced areas and that P. toxostoma became infected after contact with C. nasus. Although the genotype of P. toxostoma and recombinant genotypes of hybrids are susceptible to Dactylogyrus transmitted from C. nasus, the intensity of infection is low in these genotypes.


Asunto(s)
Biota , Cyprinidae/crecimiento & desarrollo , Cyprinidae/parasitología , Parásitos/clasificación , Parásitos/aislamiento & purificación , Animales , Francia
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