Can plants be identified by their DNA the way humans can?
Dear Straight Dope: Do different plants belonging to the same species have their own unique DNA sequences (just like us humans)? Another twist to the same question: Let’s say I have an apple. Would I be able to tell, by DNA analysis, exactly which apple tree it came from? — Habib Rahman Everything, even clonal and asexual organisms, has some difference that sets it apart from every other member of its species. The act of replicating DNA is not quite perfect, and there are always small glitches in the copying process. The trick is detecting these differences, and making use of them in a diagnostic way. Especially important is the level of variation between and within individual organisms. To use your apple example, if you actually could go in and sequence every single nucleotide in the genome of every cell in that apple, you’d find that no two cells were exactly the same. At that point, the question is this: is the level of difference between two cells in that fruit significantly less t
