Investigating different experiences of genetic genealogy research in contemporary Italy (“Toscani in Italia,” based on the collection of genotypical data, the Sardinian “genetic park,” a judicial inquiry in Lombardy) this article questions three themes: the relations between kin and ancestry, as it is perceived by the protagonists—and through their cultural elaboration—and the identity emerging from genetic profiles; the use and appropriation of these two types of identity in the communities; the problem of authenticity and truth incorporated into biological heritage, as well as that of socially recognized belonging through family names, through the various ethnic categories, and through the geography of migrations. Concepts such as “haplogroups,” genetic lineage and others of the same variety lead to an interdisciplinary encounter between social anthropology and bio-genetic classification.