1 ) similar is not the same as ' exactly the same '
2 ) Winemaking is a TraZillionDollar industrty
3 ) If Napa Vineyards are wiped out , there is a " seed-bank " at UC Davis charged w keeping , what was called in the old days , ' seeds' of all kinds stuff,
There are University run seed baks all over the USA. Geneva , NY ( operated by Cornell ) has Apples, Pears , etc They are constantly creating new
apples. I used to be a member , and you got to taste the new apples each year at the fall general meeting. NYS ( New York State ) 293
was a great apple. Some are introduced for cultivation , some are added to their orchards. Im sure UCDavis is doing similar studies w their
genetic charges. They have not yet invited me to taste these ( Table and Wine ) grapes , and I can't say if they make wine out of the wine grapes.
They now use DNA.
consider :
https://agritech.cals.cornell.edu/research-extension/tree-fruits/
https://agritech.cals.cornell.edu
we might have to drink beer for a few years, but grapes , table varieties and wine varieties are here to stay.
P.S.: take a look here ;
http://fps.ucdavis.edu/index.cfm
note the plant genome material kept at UC Davis has very high commercial value. places like this are funded both by Dot.Gov and Commercial entities.
http://fps.ucdavis.edu/fgrmain.cfm
P.P.S.: its my understanding from original literature ( in translation , of course ) that Roman Wine was a bit tart . tertiary fermentation ?
unless its was really brand new ( Tiberius Novus , very popular at the time , for a few weeks )
add-ons were the key : Honey , herbs , fermented fish ( RB1 ? ) etc.
but its a very interesting topic how Wine , etc has evolved.
I personally keep a close eye on the various bottles at TJ's