So what happens is that seed production is in the hands of one big corporation. Monsanto.
It's suing farmers for accidental cross pollination or in other words they pollute the crops of farmers with their product and then they sure them.
Farmers, thinking their production will go up, don't realize their expenses go up three times, making their profit less.
What already has happened, is that a lot of farmers use the same seeds and, oh, surprise, there was a disease that targeted their expensive crops... Aaaannnd it was all gone. The harvest of a very big region ruined. In India this has already led to whole (cotton) farmer communities to go bankrupt.
Great job GMO.
Root cause: we are with too many people on this earth. GMO will not solve that problem.