The Distinction between Conventional Breeding and Genetic Engineering

For thousands of years human beings have altered the genomes of all major crops radically and constantly to change growth and ripening characteristics, speed maturity, eliminate grain shattering, improve taste and reduce toxins, increase size, and even get rid of seeds, as in grapes and bananas. Pictures comparing the wild and cultivated types of any crop invite incredulity because the differences are so sweeping.

Crops that are very different from each other, such as Brussels sprouts, cabbage, cauliflower, and broccoli, derive from the same ancestral stock, whereas other crops, such as bread wheat and canola, are artifacts. Wheat used for bread was created when technologists about 4,000 years ago hybridized tetraploid durum wheat with an inedible goat grass. Canola (Canada oil) was fabricated in the twentieth century by Canadian biologists who assaulted and pum-meled by heat, radiation, and other means the genome of an inedible rape (mustard) plant. They selected for mutations that eliminated toxic acids and smelly glucosinolates that had made the plentiful rapeseed oil unpalatable. Every cultivar has a story of genetic manipulation and hybridization that explains its stark differences from its wild ancestors. Some of those stories, such as those of kiwi fruit, strawberry, and tomato, suggest that one can make the agronomic equivalent of a silk purse out of a sow's ear.

To assess ethical objections to agricultural biotechnology one must distinguish concerns that apply to forced mutation, hybridization, and artificial selection generally from those that apply only to the changes—often small by comparison—associated with genetic manipulation (GM). Because conventional breeding techniques have become more sophisticated and in principle may be able to achieve (although more arduously) the same mutations that GM accomplishes easily, the boundary between old and new biotechnologies may be hard to draw. The principal difference may be this: GM performs "outcrosses" that take advantage of the apparent fact that all life has the same origin, whereas conventional techniques cross species that are more closely related or apply pressure to a genome to induce hoped-for changes.

Anxiety and Depression 101

Anxiety and Depression 101

Everything you ever wanted to know about. We have been discussing depression and anxiety and how different information that is out on the market only seems to target one particular cure for these two common conditions that seem to walk hand in hand.

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