Mitochondrial haplogroup U5b3: a distant echo of the epipaleolithic in Italy and the legacy of the early Sardinians.
There are extensive data indicating that some glacial refuge zones of southern Europe (Franco-Cantabria, Balkans, and Ukraine) were major genetic sources for the human recolonization of the continent at the beginning of the Holocene. Intriguingly, there is no genetic evidence that the refuge area located in the Italian Peninsula contributed to this process. Here we show, through phylogeographic analyses of mitochondrial DNA (mtDNA) variation performed at the highest level of molecular resolution (52 entire mitochondrial genomes), that the most likely homeland for U5b3-a haplogroup present at a very low frequency across Europe-was the Italian Peninsula. In contrast to mtDNA haplogroups that expanded from other refugia, the Holocene expansion of haplogroup U5b3 toward the North was restricted by the Alps and occurred only along the Mediterranean coasts, mainly toward nearby Provence (southern France). From there, approximately 7,000-9,000 years ago, a subclade of this haplogroup moved to Sardinia, possibly as a result of the obsidian trade that linked the two regions, leaving a distinctive signature in the modern people of the island. This scenario strikingly matches the age, distribution, and postulated geographic source of a Sardinian Y chromosome haplogroup (I2a2-M26), a paradigmatic case in the European context of a founder event marking both female and male lineages.
Pala
Maria
M
Dipartimento di Genetica e Microbiologia, Università di Pavia, Pavia, Italy.
Achilli
Alessandro
A
Olivieri
Anna
A
Hooshiar Kashani
Baharak
B
Perego
Ugo A
UA
Sanna
Daria
D
Metspalu
Ene
E
Tambets
Kristiina
K
Tamm
Erika
E
Accetturo
Matteo
M
Carossa
Valeria
V
Lancioni
Hovirag
H
Panara
Fausto
F
Zimmermann
Bettina
B
Huber
Gabriela
G
Al-Zahery
Nadia
N
Brisighelli
Francesca
F
Woodward
Scott R
SR
Francalacci
Paolo
P
Parson
Walther
W
Salas
Antonio
A
Behar
Doron M
DM
Villems
Richard
R
Semino
Ornella
O
Bandelt
Hans-Jürgen
HJ
Torroni
Antonio
A
D041322:Chromosomes, Human, Y / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D005828:Genetics, Population; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007558:Italy; D008297:Male; D008969:Molecular Sequence Data; D010164:Paleopathology; D010375:Pedigree
D004272:DNA, Mitochondrial