Jogro
Well-Known Member
If we're going to be strict with our terms here, then the "gene pool" by definition is the sum total genes present in the species. So by the book, ALL cannabis plants come from the same gene pool. . .even feral Siberian hemp and "Girl Scout Cookies".
Again, when it comes to crosses, the cannabis genome is over 500Mb in size about 400 million base pairs, and contains multiple thousands of individual genes most of which will potentially assort independently during sexual crosses. Now, most of these are stable or involved with plant internal machinery and aren't part of any externally visible phenotype of interest to medical breeders/growers.
But of the phenotypic expression interesting to breeders/growers many of these traits (eg plant size, structure, potency, flavor, etc) aren't controlled by one gene, but by combinations of many genes that may not interact in straightforward Mendellian inheritance patterns.
Also, even if we concede that a given gene Aa and aA are functionally identical to each other and to AA, but different than aa, what about B, C, D, E, F, G, H, I, J, etc?
If you're looking at just TEN individual genes, each with classic attached dominant/recessive Mendelial phenotypes, then a simple F2 cross of simple F1 hybrid plants heterozygous at each of the ten loci could potentially yield 1000 different phenotypes! If there are more than two possible genes or phenos for any given locus/trait (eg you're talking about a polyhybrid) the possible number of phenotypes can go up geometrically.
The point is, again, depending on the genetics involved, crossing any two plants (or the same plant to itself) can potentially result in offspring all similar to each other and the parent, to a few distinct phenotypes, to potentially MANY different phenos, some of which may express "new" traits not seen in the parent/s.
I think the single biggest misconception with regards to cannabis genetics. . .one deliberately promulgated by ceed companies. . .is that S1 ceeds are genetically similar/identical to the parent. Again, in almost ALL cases this is NOT true. Except under fairly limited circumstances you CANNOT EXPECT THE OFFSPRING OF A SELF-CROSSED/S1 PLANT TO BE THE SAME AS THE PARENT.
Its only true if the parent is inbred, and in a case like that there is probably no need to make S1 seeds, because a similar line male parent can probably be identified.
If the parent is partially inbred (ie its parents are related), you may see only a limited number of phenos, many of which are like the parent.
But in most cases where people are making S1s, its because the parent plant is NOT inbred, and ITS parents are either unknown, unavailable, unstable, or some combination of the above. These are typically desirable "clone only" plants.
