Presentation on theme: "Ancient DNA signatures in modern breeds"— Presentation transcript:
1 Ancient DNA signatures in modern breeds Paolo Ajmone MarsanUniversità Cattolica del S. Cuore, Piacenza, Italy
2 One past revealed to us in many ways No source is unbiased…..
3 Integration of disciplines When combining records in a synthesis, their unique characteristics are to be considered:Makers of a certain style of pottery may have left no descendants…..Artifacts can move through trade, with no gene flow….Gene flow can occur across languages……..………..Records are independent reflextion of a single pastbut they need not all tell us the same thing!
4 Different strata of the past are accessible through the analysis of genetic diversity Phylogenetic relationship between species and the origin of the tree of lifePrehistorical migrationsHistorical migrationsGenealogical studiesPaternity testingIndividual identificationPRESENT
5 Since domesticationDomestic animalsmolecular genetics
6 DNA diversityVariation among modern individuals is shaped by cumulative past processesExtracting information on any one past period or events requires careful interpretation, to isolate it from previous and subsequent processesNeutral markers are perhaps the most representative records of the past, not biased by natural/human selection
7 Please, notice, no cellular phone European projectRESGEN EU project (PL98-118)Towards a strategy for the conservation of genetic diversity in European cattleTowards a strategy for the conservation of the genetic diversity of European cattlePlease, notice, no cellular phone(www.androclus.vet.uu.nl/resgen/)
13 Relationship among Italian breeds -0,2-0,15-0,1-0,050,050,10,15It, FresianItalian Red PiedValdostana Red PiedCabanninaIt. LimousineRendenaPiedmonteseMucca PisanaPodolicaMaremmanaCinisaraIt. BrownModicanaMarchigianaRomagnolaChianinaCalvanaAlpine GreyNORTHCENTRE-SOUTHPCOA1ALPINEPCOA2PODOLIAN
25 Central Italian breeds seem to share a different Centre EuropeNear EastItalyMPD3.5±1.84.0±2.03.6±1.9MPD1.9±1.12.0±1.41.5±1.2Central Italian breeds seem to share a differenthistory compared to that of other Italian breeds
29 Relationship among Italian breeds -0,2-0,15-0,1-0,050,050,10,15It, FresianItalian Red PiedValdostana Red PiedCabanninaIt. LimousineRendenaPiedmonteseMucca PisanaPodolicaMaremmanaCinisaraIt. BrownModicanaMarchigianaRomagnolaChianinaCalvanaAlpine GreyNORTHCENTRE-SOUTHPCOA1ALPINEPCOA2PODOLIAN
30 Historical information L. IUNIUS MODERATUS COLUMELLA (I sec A.C.)De Re Rustica - Liber VI“[…] l’Umbria ne produce di grandissimi e bianchi (Umbria produces huge and white (bovines)); ma anche di rossicci, non meno pregiati sia come indole sia come struttura fisica. L'Etruria ed il Lazio li hanno tarchiati, ma forti nel lavoro. Gli Appennini danno bovini robustissimi […]”In VI – VII sec. B.C. Numa Pompilio (Roman king) introduced in Rome the use of sacrifying to gods huge white bovines used in field workingRomans called the elephants taken by Hannibal “bulls from Lucania” (about 215 B.C.).
31 Small size of domestic bovines Iron age: 1,10 – 1,20 mBos primigenius: 2,20 – 2,30 m
32 Is there any link with the onset of Etruscan civilisation?
33 Etruscan had a powerful military and trading fleet and reached the Aegean sea and Anatolia Strabone, citing Eforo, reports that Greeks that were founding Naxos (734 B.C.) were afraid of Etruscan attacks.
34 Etruscan navy controlled trade in west Mediterranean 630 – 500 a.C.
35 Distribution of etruscan ceramics with red figures 350 – 270 B.C.
36 Cultural exchange with Greeks The Oriental period (VIII - VI sec. a.C.)Wine makingOlive pressing to obtain olive oilCrop rotationMetallurgyCeramicsCrafting
38 the origin of this civilisation On-going debate onthe origin of this civilisationLocal development, with Eastern influencesor Eastern Mediterranean provenience?History -> HerodotusLinguistics -> European or Semitic?Archaeology -> different opinionsWhat about genetics?
39 Genetic data from modern populations Francalacci et al. (1996 Am. J. Phys. Anthropol. 100, ) modern mtDNA sequences suggested the presence in Tuscany of an ancient European mtDNA diversity component, subsequently enriched by migrational waves, possibly from the Middle East.Cavalli-Sforza and coauthors assayed nuclear markers in modern humans living in Tuscany (1994 History and geography of human genes - Princeton University Press, Princeton, NY, USA). They detected a genetic discontinuity in these when compared to nearby Italian populations, explained either as an immigration from elsewhere or by the ancient expansion of a local isolated population.
40 mtDNA analysis from Etruscan remains (Vernesi et al., 2001 Proc. Natl. Acad. Sci. USA 98,Most related modern populationmodern TuscansAnatolia populationsGene flow with
41 Extended analyses Dataset of cattle mitochondrial sequences 237 Bos taurus mtDNA sequences from animals reared in Continental Europe, Anatolia, Near East and Africa. Total bovine mtDNA dataset comprising 401 sequences.Dataset of human mitochondrial sequencessequences of Homo sapiens mtDNA HVRI region Sequences of populations living in the same regions of cattle sampling were retrieved
46 Bovine vs Human genetic distances (r = 0.98; Mantel test = 0.99).
47 Admixture analysis Parental population Hybrid population Africa Europe Anatolia & Near EastNorthern Italy0.071 ± 0.0871.114 ± 0.364± 0.442Central Italy0.028 ± 0.0840.160 ± 0.2970.812 ± 0.363Southern Italy0.197 ± 0.0981.517 ± 0.405± 0.486
48 Conclusion 1Likely arrival of progenitors of Central Italian bovines from Eastern Mediterranean by the sea-route:significant presence of haplotype variants typical of the Near East (T, T1 and T2), but rare or absent in Europe;close genetic relationship between Central Italian, Anatolian and Near Eastern T3 haplogroup;sudden burst of diversity detected in Central Italian cattle, observed nowhere else in the Italian peninsula;statistical support by the comparison of the level of genetic diversity in the different areas investigated;major contribution of Anatolian and Near Eastern Bos taurus to Central Italian cattle mtDNA is confirmed by admixture analysis.
49 Conclusion 2The migration hypothesis better explains the finding of parallel signatures in humans and cattle. Outlier behaviour points to the same direction: highly significant correlation between human and cattle genetic distance matrices.Alternative hypothesis: trade. In this case only or mainly bovine mtDNA is expected to carry clear Eastern molecular signature. Data of Vernesi et al., Francalacci et al., and the MDS results support the conclusion that modern people from Tuscany possess mtDNA more related to Anatolian and Near Eastern populations than to Europeans.
50 Migrational event should pre-date the Roman age Conclusion 3Migrational event should pre-date the Roman agePresence of the same cattle breeds in Central Italy at least since the I century B.C.No later records of large import of cattle females and massive human immigrations from Eastern Mediterranean shores in Tuscany.Sea freight of bovines was technically possible. Not a huge number of animals had to be transported from the Near East (high variability in Near East and population expansion contrasting the loss of haplotypes by genetic drift)
51 Conclusion 4The event is unlikely to date back to the Neolithic colonization of Italy (around 6,000 B.C.).This process began in the southern part of the peninsula, where people arrived from the Balkans and gradually spread northward.Archaeological remains from Italy are in favour of a relative cultural homogeneity until the Bronze Age (2nd millennium B.C.)
52 Conclusion 4The period in which, likely, the Eastern migration occurred is compatible with the onset of the Etruscan civilisation (X-IX sec B.C.).These data support the Eastern origin of Etruscans, as reported by Herodotus (1.94) in the V century B.C.Near Eastern populations and their cattle should have sailed and docked to Central Italy. The admixture of people and animals with autochthonous Italian populations have likely originated the embryo of Etruscan culture.Before Rome…..All roads took nearby….. To Tarquinia (or Caere, Cerveteri, Chiusi…)?