All our food comes from stuff that's been alive: animals, plants or microbes.

Humans get food by hunting & gathering wild animals, plants or microbes, or by domesticating 
animals into livestock or cultivating plants into crops and developing microbes into microbial 
cultures (such as for yogurt).

The act of hunting & gathering, and of domesticating & cultivating, is a human selection process that changes the genetic makeup of the populations of animals, plants and microbes we eat.

Why try to improve crops & livestock? 
Not all plants, animals or microbes serve humans equally well as food.

Humans select or develop crops, livestock and microbial cultures based on traits favorable to 
humans.

Those favorable traits include taste, color, ease of preparing, yield, vigor, storability, and nutrition.

Manipulating Genes, Manipulating Environment 
Biologists hold that the traits, or the phenotype, of living things result from the interaction of the 
genotype--the genes of an organism--and the environment in which the organism lives.

To generate better varieties of crops, livestock and microbes, humans can manipulate the genes, humans can modify the environment, or humans can modify both the genes and the environment.

So all livestock, crops and cultures have genes, and all are genetically modified by any ordinary 
meaning of 'genetically' and 'modified' but they are not all gene-spliced. This is why I think it is a misnomer to use the common term "genetically modified organism" to refer only to gene-spliced organisms.

Expanding the Gene Pool, Improving Ways to Select Seedstock 
To generate new varieties through breeding, a breeder requires a source of genetic variation.

Genetic variation is expressed in the term "gene pool": all the genes available to a breeder useful in improving a breed through generating combinations of genes that result in superior traits.

The breederâs bread and butter are 1) the gene pool and 2) the methods for selecting and 
manipulating individuals or populations to get new varieties with more desirable traits.

In nature, genes mutate and genes flow and recombine from generation to generation within a 
species. Genes flow among unrelated species through transformation, transduction, conjugation, cell fusion, and viral infection.

Until 1973, the gene pool for a corn breeder was limited to corn and its close relatives that could cross-pollinate with it.

A Dozen Ways to Change & Move Genes 

Plant breeders genetically manipulate plants many ways, including these 12: 

• Selection 
• Breeding 
• Cloning 
• Grafting 
• Hybridization 
• Mutagenesis 
• Tissue Culture
• Somaclonal Variation
• Embryogenesis
• Cell Fusion
• Transposons
• Viral Infection

DNA provides other ways, independently of gene-splicing, for improving the selection of seedstock, such as gene mapping and marker-assisted selection.

Finding and Moving DNA, the Carrier of Genes 
Recombinant DNA has been around since before humans. Cells have enzymes and other materials for making, copying, splicing and transferring DNA. In researching how cells use the enzymes to make and move DNA, scientists discovered ways to use the cell's enzymes to design and move DNA.

While recombinant DNA has been around since before humans, recombinant DNA technology is about 30 years old. It is one of the most powerful tools ever invented. The gene-splicing tools are used to copy and move gene-carrying pieces of DNA from one species to a completely unrelated organismöor, given our understanding of life on Earth, perhaps it is more accurate to say a distantly related organism.

Comparing the Risks of Various Methods of Genetic Modification 

The changing and moving of DNA, that is, the changing and moving of genes, by nature alone or by the hands of humans present risks of changing the traits for ill as well as for good.

Recombinant DNA technology gave even leading scientists pauseöand cause to ask a series of questions: 

• Is it safe? 
• Or better: Is it safe enough? 
• Or better still: How safe or risky is it compared to other methods of genetic modification?

"Is it safe enough?" Well, the judgement of scientists with the National Academy of Science and with the World Health Organization is that the existing evidence is that risks of gene-splicing are not different from and no greater than the risks of other methods of genetic manipulation.

Succinctly, foods from gene-spliced crops are as safe as foods from conventionally-bred crops, for the same trait. 

And some scientists argue that gene-spliced crops are actually safer.

The range of other concerns includes environmental, social, ethical and legal issues.

If the concern is not based on a risk unique to gene-splicing, then one should look for comparable scrutiny for comparable risk. If the focus is always on biotech while ignoring or discounting risks from other methods of genetic modification, then one might want to ask, Why the one-sided scrutiny?