Approach
Scientists have taken the logical step of trying to introduce genes directly into human cells, focusing on diseases caused by single-gene defects, such as cystic fibrosis, haemophilia, muscular dystrophy and sickle cell anemia. However, this has proven more difficult than modifying bacteria, primarily because of the problems involved in carrying large sections of DNA and delivering them to the correct site on the gene. Today, most gene therapy studies are aimed at cancer and hereditary diseases linked to a genetic defect. Antisense therapy is not strictly a form of gene therapy, but is a related, genetically-mediated therapy.
The most common form of genetic engineering involves the insertion of a functional gene at an unspecified location in the host genome.This is accomplished by isolating and copying the gene of interest, generating a construct containing all the genetic elements for correct expression, and then inserting this construct into a random location in the host organism. Other forms of genetic engineering include gene targeting and knocking out specific genes via engineered nucleases such as zinc finger nucleases, engineered I-CreI homing endonucleases, or nucleases generated from TAL effectors. An example of gene-knockout mediated gene therapy is the knockout of the human CCR5 gene in T-cells in order to control HIV infection. This approach is currently being used in several human clinical trials.
Read more about this topic: Gene Therapy
Famous quotes containing the word approach:
“Every man alone is sincere. At the entrance of a second person, hypocrisy begins. We parry and fend the approach of our fellow-man by compliments, by gossip, by amusements, by affairs. We cover up our thought from him under a hundred folds.”
—Ralph Waldo Emerson (1803–1882)
“There is no calm philosophy of life here, such as you might put at the end of the Almanac, to hang over the farmer’s hearth,—how men shall live in these winter, in these summer days. No philosophy, properly speaking, of love, or friendship, or religion, or politics, or education, or nature, or spirit; perhaps a nearer approach to a philosophy of kingship, and of the place of the literary man, than of anything else.”
—Henry David Thoreau (1817–1862)
“We have learned the simple truth, as Emerson said, that the only way to have a friend is to be one. We can gain no lasting peace if we approach it with suspicion or mistrust or with fear.”
—Franklin D. Roosevelt (1882–1945)