Confirms theory that M26 likely represents aboriginal Italians.
In 2009, Maria Pala et al first put out the theory that YCC Hg I-M26 represented the aboriginal Italians, who had stayed in a small Italian refugium during the LGM. The paper was called "Mitochondrial Haplogroup U5b3: A Distant Echo of the Epipaleolithic in Italy and the Legacy of the Early Sardinians" and can be found here. It was kind of an added bonus theory in the paper, which focused on mtDNA but put forth the idea en passant.
Now, a landmark study on Italian Y chromosomes shows significant I-M26 in the archaic Samnium region of Italy. This is and was always a rugged, remote, mountainous part of Italy known even in Roman times as being populated by some of the earliest inhabitants of Italy. This, coupled with what American genetic genealogists already knew (which is the presence of M26 in many males from remote parts of mountainous northern Calabria), would seem to confirm the theory that M26 was present in an Italian refugium during the epipaleolithic. And that those people went on to populate Sardinia and other coastal regions of southwest Europe.