's announcement in February 2010 di DNA mitocondriale ricavato da un osso fossile dalla Siberia era intrigante: la serie di nucleotidi non coincideva con nessuna delle specie di ominidi che si riteneva popolavano la zona 30.000 anni fa - H. sapiens e H. neanderthalensis.
Dopo i primi risultati si ha proseguito nella ricerca, cercando di ricavare materile genetico del nucleo delle cellule dallo stesso reperto. I ricercatori sono rimasti piacevolmente sorpresi, il materiale recuperato era estremenente puro, 70% del DNA (a differenze di una media di pochi percentili in casi analoghi) puó essere attribuito all´ominidi di Denisova.
Gr azie al materiale genetico si ha potuto avvalorare l´ipotesi che il new hominid is a distinct strain that is separated from a common ancestor with the Neanderthals about 300,000 years ago.
Moreover, comparing the DNA sequence data with modern man, we found similarities with the indigenous peoples of Papua New Guinea - Indonesia.
The model developed on these data assumes that the hominid Denisova has first developed in Central Asia by hominids migrated from Africa. Here two lineages have separated - a brought a Neanderthal man who has focused mainly in western Asia and Europe, the other line of evolution over time has shifted eastward.
The DNA research has found further fossil attributed to the new human strain, a large molar, possibly a male hominid, showed a genetic sequence very similar to that of the phalanx bone examined.
Dopo i primi risultati si ha proseguito nella ricerca, cercando di ricavare materile genetico del nucleo delle cellule dallo stesso reperto. I ricercatori sono rimasti piacevolmente sorpresi, il materiale recuperato era estremenente puro, 70% del DNA (a differenze di una media di pochi percentili in casi analoghi) puó essere attribuito all´ominidi di Denisova.
Gr azie al materiale genetico si ha potuto avvalorare l´ipotesi che il new hominid is a distinct strain that is separated from a common ancestor with the Neanderthals about 300,000 years ago.
Moreover, comparing the DNA sequence data with modern man, we found similarities with the indigenous peoples of Papua New Guinea - Indonesia.
The model developed on these data assumes that the hominid Denisova has first developed in Central Asia by hominids migrated from Africa. Here two lineages have separated - a brought a Neanderthal man who has focused mainly in western Asia and Europe, the other line of evolution over time has shifted eastward.
The DNA research has found further fossil attributed to the new human strain, a large molar, possibly a male hominid, showed a genetic sequence very similar to that of the phalanx bone examined.
Fig.1. phylogenetic tree of mitochondrial DNA analysis (click to enlarge), in gray the 54 representatives of H. modern sapiens (that an individual fossil) in the 6 individuals of blue H. neanderthalensis in red and the hominid Denisova, on the right side of the geographical origin of the material analyzed (by KRAUSE et al. 2010). NB: Images are taken from the publication in risoluzione minore per soli scopi di discussione e didattica. Bibliografia:
REICH. D. GREEN, R.E.; KIRCHER, M.; KRAUSE, J.; PATTERSON, N. et al. (2010): G enetic history of an archaic hominin group from Denisova Cave in Siberia. Nature 468: 1053-1060
KRAUSE et al. (2010): The complete mitochondrial DNA genome of an unknown hominin from southern Siberia. Nature online publication 24 March 2010: doi:10.1038/nature08976
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