If you want to find out what kind of potato you are dealing with from the DNA of a potato leaf. So based on the plant that grows out of the potato, you want to see what the potato looks like.
I know that you first have to isolate the DNA and then double it and put it in a gel to let the DNA ‘run’. But how exactly does this work, and what steps do you need to take?
Answer
Dear Mallory,
I think you are asking about a test to determine which variety you are dealing with on the basis of DNA from a potato leaf.
Various genetic tests are possible for this. They all work analogously.
I explain the simplest: RFLP (restriction fragment length polymorphisms). This test is actually used to compare closely related species. Comparisons within the same species are made with a different test, but the principle is analogous.
- isolate DNA from a potato plant
- cut the DNA with 2 restriction enzymes. These enzymes cut the DNA at known sites. The DNA is cut into smaller fragments. Because each race has a slightly different DNA code, the enzymes will cut in different places and so you get fragments of different lengths.
- run the DNA on a gel. You will see straps of different sizes. The pattern is typical of a breed
- compare the gel pattern with the patterns of known varieties. If your pattern matches that of a known race, you know for sure that you have that race.
DNA duplication is not necessary in this type of testing.
regards
Answered by
dr. ir. Tim Wings
Plant breeding, Molecular Genetics, clover, progeny, quinoa, seed cultivation
Burg. van Gansberghelaan 96 box 1 9820 Merelbeke
http://www.ilvo.vlaanderen.be
.