AFAIK, all efforts with hybridization have had very limited succes, if that.
Actually I am not optimistic about this approach, but it is not my field

As to gene splicing, who knows? However, if this succeeds will the result
still be recognizable as American elm or American chestnut?
PvR

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Iris Cohen schreef
Do you suppose they will ever be able to breed disease resistance into the
American elm or American chestnut through gene splicing, or will we have to
be satisfied with introgressed hybrids?
Iris,

Maybe, but these are notably poor examples. Both Zea mays and Homo sapiens
are species only by agreement and notably rich in forms, rich enough to make
several species in a different context.
PvR

Why not? The corn with the insecticidal Bacillus gene is still Zea mays.
Joe Jones who is treated for Parkinson's disease with gene therapy is still
Joe Jones, as well as Homo sapiens sapiens.
Iris