In 2013 I explained in my Genetic history of the Italians that the ancient Italic tribes, including the Latins/Romans would have belonged primarily to R1b-U152 (especially Z56). I mentioned that the original Latins of the Roman Republic would also have carried G2a-L140 (specifically the L13, L1264 and Z1816 subclades) as well as some yet unidentified J2a subclades. I have just updated the phylogenetic tree of Y-haplogroup J2 and I came across a branch that appeared to be the ideal candidate for the Italic J2a1. That branch is Z435, immediately downstream of L70.
All L70 carriers today descend from a single patrilineal ancestor who lived about 5,000 years ago, when the Proto-Indo-Europeans started invading Central Europe from the Pontic Steppe. Indeed, a lot of J2a1-L70 are now found in Northeast Europe and Central Asia, which suggests an Indo-European dispersal from the steppes.
Z435 has a TMRCA of only 3,100 years, which corresponds roughly to the timing of the invasion of Italian peninsula by Italic tribes from the Alps. Z435 has numerous subclades of its own, and most have been identified in central Italy. The PF5456 subclade is barely 2500 years old, and would have emerged and propagated after the founding of Rome. Outside Italy, it is now found in such varied places as Spain, France, England, Belgium, southern Germany, Austria, Bulgaria or Tunisia, all regions colonised by the Romans. It would be very hard to explain how this 2500 year-old clade spread so far and wide around Europe if it weren't for the Romans.
Z2177, another subclade of Z435, is a bit under 3,000 years old and, although rare, it is found today in places like Tuscany, Sardinia and Spain, which also suggests a Roman connection.
Here is the relevant section of the J2a1-L26 tree:
All L70 carriers today descend from a single patrilineal ancestor who lived about 5,000 years ago, when the Proto-Indo-Europeans started invading Central Europe from the Pontic Steppe. Indeed, a lot of J2a1-L70 are now found in Northeast Europe and Central Asia, which suggests an Indo-European dispersal from the steppes.
Z435 has a TMRCA of only 3,100 years, which corresponds roughly to the timing of the invasion of Italian peninsula by Italic tribes from the Alps. Z435 has numerous subclades of its own, and most have been identified in central Italy. The PF5456 subclade is barely 2500 years old, and would have emerged and propagated after the founding of Rome. Outside Italy, it is now found in such varied places as Spain, France, England, Belgium, southern Germany, Austria, Bulgaria or Tunisia, all regions colonised by the Romans. It would be very hard to explain how this 2500 year-old clade spread so far and wide around Europe if it weren't for the Romans.
Z2177, another subclade of Z435, is a bit under 3,000 years old and, although rare, it is found today in places like Tuscany, Sardinia and Spain, which also suggests a Roman connection.
Here is the relevant section of the J2a1-L26 tree: