Unit 3 New

Many human diseases are caused by the absence or inappropriate presence of a protein. Biotechnology's first promise was to isolate and produce these natural proteins through genetic engineering and recombinant technology. The protein could then be administered to patients in order to compensate for its absence. Because proteins are not orally available, biotech companies focused on innovative methods of protein delivery and sustained drug delivery.
Unit 3
Gene Therapy
Word Formation
aden/o (gland) e.g. adenovirus -ase (enzyme) leuk/o (white) e.g. leukemia syn- (together with) e.g. syndrome poly- (multiple) e.g. multigene mono- (single) e.g. monocyte homo- (the same) e.g. homograft homosexuality chrom/o (colour) e.g. chromosome -some (body) e.g. somatic
Understanding the Text
Para. 1 • gene • chromosome • physical • heredity • sequences of bases
• encode / encoded • genetic disorder
Para. 2 • defective/faulty genes • nonspecific location • a nonfunctional gene • genome • swap: to exchange 置换，交换， 掉换 e.g. I’d swap my job for hers any day. 我愿随时和她调换工作。 • homologous recombination • selective reverse mutation • regulation
Gene therapy is the introduction of genetic material into cells for therapeutic purposes. Recent scientific breakthroughs in the genomics field and our understanding of the important role of genes in disease has made gene therapy one of the most rapidly advancing fields of biotechnology with great promise for treating inherited and acquired diseases.
What is gene therapy? Gene therapy is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient’s cells instead of using drugs or surgery. Researchers are testing several approaches to gene therapy, including:
• Gene therapy in germline cells has the potential to affect not only the individual being treated, but also his or her children as well. Germline therapy would change the genetic pool of the entire human species, and future generations would have to live with that change. In addition to these ethical problems, a number of technical difficulties would make it unlikely that germline therapy would be tried on humans in the near future.
Although gene therapy is a promising treatment option for a number of diseases (including inherited disorders, some types of cancer, and certain viral infections), the technique remains risky and is still under study to make sure that it will be safe and effective. Gene therapy is currently only being tested for the treatment of diseases that have no other cures.
retr/o ( at the back, behind) e.g. retrovirus path/o (illness) e.g. pathogen -genic (produced by) e.g. pathogenic lip/o (fat) e.g. liposome auto- (self) e.g. autonomy, autonomously tox/o (toxin) e.g. toxicity arthr/o (joint) e.g. arthritis fibr/o (fibre) e.g. fibrosis
Para. 4 • unload into: release into • generation • restore to • e.g. 治疗性基因生成新一代功能性蛋白质使靶细胞 恢复到正常状态。
Para. 6 • retroviruses:逆转录酶病毒
• double-stranded:双链
• integrated:整合 • host cell
Para. 3 • carrier / vector • therapeutic gene • target cell • genetically altered • evolve a way of：develop a way of 具备…途径 • encapsulate：把…密封于… ；压缩 • capability • manipulate: to use or control sth. with skill
Para. 8 single-stranded DNA viruses: 单链DNA病毒 chromosome 19:
19号染色体
The 24 human chromosome territories during prometaphase in fibroblast cells.
Para. 9 • herpes simplex virus type 1: I型单纯疱疹 • cold sores 感冒疮; 唇疱疹 Cold sores are small, painful, fluid-filled blisters or sores that appear on the lips, mouth, or nose that are caused by a herpes simplex virus infection. The sores can be painful and usually last a few days. Unlike most viral infections, the cold sore virus is not completely eliminated by the body defenses. For this reason, cold sores often recur.
Questions to consider:
1. What is a gene ? 2. What comment on gene therapy.
• What is a gene ? the basic unit of genetic material, which is carried at a particular place on a chromosome. Originally it was regarded as the unit of inheritance and mutation but is now usually defined as a sequence of DNA or RNA that acts as the unit controlling the formation of a single polypeptide chain.
• The types of gene therapy described thus far all have one factor in common: that is, the tissues being treated are somatic (somatic cells include all the cells of the body, excluding sperm cells and egg cells). In contrast to this is the replacement of defective genes in the germline cells (which contribute to the genetic heritage of the offspring).