What changed in the last quarter of the 20th century was that scientists began selecting productive traits at the individual gene level and controlling the placement of genes in new crops.
GMOs in modern times
The first step to develop GMOs in Modern times took by Robert Bakewell in 18th century. This was the origin of establishing of selective breeding as a scientific. Arguably, his most important breeding program was with sheep. Using native stock, he was able to quickly select for large, yet fine-boned sheep, with long, lustrous wool. The Lincoln Longwool was improved by Bakewell, and in turn the Lincoln was used to develop the subsequent breed, named the New (or Dishley) Leicester. It was hornless and had a square, meaty body with straight top lines.
Breeding cattle was the next plan that Bakewell worked on to be used primarily for beef. Previously, cattle were first and foremost kept for pulling ploughs as oxen , but he crossed long-horned heifers and a Westmoreland bull to eventually create the Dishley Longhorn. As farmers followed his directions more and more, they raised increasingly giant animals in size and quality.
In 1700, the average weight of a bull sold for slaughter was 370 pounds (168 kg). By 1786, that weight had more than doubled to 840 pounds (381 kg). And after his death, short horns replace long horns by other farmers.
The other person who helped GMOs to progress, was Charles Darwin. Darwin invented the term 'selective breeding' in the 1859 and was interested in the process as an illustration of his proposed wider process of natural selection. Darwin noted that many domesticated animals and plants had special properties that were developed by intentional animal and plant breeding from individuals that showed desirable characteristics, and discouraging the breeding of individuals with less desirable characteristics. All works that Darwin done about GMOs was theoretically.
However, the other person who widely have role in progress of the scientific study of GMOs, was an Austrian monk Gregor Mendel. His main study was on genes in 1860s when he systematically crossed varieties of garden peas. He introduced the concept of a “gene” as a unit of heredity.
Mendel worked with seven characteristics of pea plants: plant height, pod shape and color, seed shape and color, and flower position and color. Taking seed color as an example, Mendel showed that when a true-breeding yellow pea and a true-breeding green pea were cross-bred their offspring always produced yellow seeds. However, in the next generation, the green peas reappeared at a ratio of 1 green to 3 yellow. To explain this phenomenon, Mendel coined the terms “recessive” and “dominant” in reference to certain traits.
In 1868, German chemist Friedrich Meischer discovered the substance we now call DNA, Deoxyribose Nucleic Acid. But scientists thought it was too simple chemically to carry the vast amount of genetic information required to produce the enormous diversity of nature. But this discovery was a real revolution and those proteins, they thought, were the basis of genetics.
In 1944, Oswald Avery tentatively identified DNA as the true carrier of molecular information, and his findings were confirmed in 1952.
1954. Watson and Crick described DNA’s shape as a double helix, paving the way for genetic engineering to make a real debut…