Fish Genetics and Breeding Learning Module PDF

**FISH 8. FISH GENETICS AND BREEDING** **Learning Module in Advances in Fish Genetics** **Module Overview** This module will delve into the exciting field of fish genetics, focusing on recent advancements such as gene transfer and transgenic fish. It will explore the potential benefits and risks...

**FISH 8. FISH GENETICS AND BREEDING** **Learning Module in Advances in Fish Genetics** **Module Overview** This module will delve into the exciting field of fish genetics, focusing on recent advancements such as gene transfer and transgenic fish. It will explore the potential benefits and risks associated with these technologies, as well as the ethical considerations surrounding their use. **Learning Objectives** Upon completion of this module, students will be able to: 1. Explain the techniques used in gene transfer and transgenic fish development. 2. Evaluate the potential applications of genetic engineering in aquaculture and Fisheries. 3. Discuss the ethical implications and biosafety concerns related to GMOs. **Recombinant DNA Technology** - In 1970, Stanford University's Paul Berg invented the first "recombinant DNA" by combining fragments from different organisms. - He thereby created the first DNA molecule made of parts from different organisms. - This type of molecule became known as \"**hybrid DNA\" or \"recombinant DNA\".** - In 1973, Herbert Boyer and Stanley N. Cohen introduced recombinant DNA technology, demonstrating that genetically engineered DNA molecules could be multiplied in a foreign cell. - Recombinant DNA Technology is a technology of joining together of DNA molecules from two different species that are inserted into a host organism to produce new genetic combinations. - Recombinant DNA technology involves using enzymes and various laboratory techniques to manipulate and isolate DNA segments of interest. - This method can be used to combine (or splice) DNA from different species or to create genes with new functions. The resulting copies are often referred to as recombinant DNA. Recombinant-DNA-technology.jpg **Basic Principle of Recombinant DNA Technology**  The image illustrates the key steps involved in recombinant DNA technology, a powerful technique used to manipulate and engineer genetic material. The first step is to identify the specific gene that you want to manipulate. This could be a gene from a human, animal, plant, or even a microorganism. Then the gene of interest is isolated from the source organism using techniques like restriction enzyme digestion. Restriction enzymes are molecular scissors that cut DNA at specific sequences. A plasmid, a small circular piece of DNA, is used as a vector to carry the gene of interest into a host cell. The plasmid is also cut with the same restriction enzyme used to isolate the gene, creating complementary sticky ends. The gene of interest and the cut plasmid are mixed together. DNA ligase, an enzyme, joins the complementary sticky ends of the gene and the plasmid, forming a recombinant DNA molecule. The recombinant plasmid is introduced into a host cell, often a bacterium. This process, called transformation, allows the bacteria to take up the plasmid. Once inside the bacterial cell, the recombinant plasmid replicates along with the bacterial DNA, producing many copies of the gene of interest. The bacterial cell can also express the gene, producing the protein encoded by the gene. **Tools Used in Recombinant DNA Technology** **Restriction Enzymes** These are molecular scissors that recognize and cut specific DNA sequences. They are crucial for isolating the desired gene from the source organism\'s DNA. **Ligase** Ligase is an enzyme that acts as a molecular glue, joining the cut ends of DNA fragments. It is used to insert the isolated gene into a vector, such as a plasmid. **Vectors** Vectors are DNA molecules that can carry foreign DNA into a host cell. Common vectors include plasmids, viruses, and artificial chromosomes. They ensure the replication and expression of the inserted gene. **Suitable Host** A suitable host organism, often a bacterium like *E. coli*, is selected to receive the recombinant DNA. The host provides the necessary environment for the replication and expression of the gene.  **Processes of Recombinant DNA Technology (Has five steps)** **1. Isolation of DNA:** - The first step is to extract DNA from the organism of interest. This involves breaking open cells and purifying the DNA using various techniques.   **2. Cutting of DNA at Specific Locations:** - Restriction enzymes are used to cut the DNA at specific sequences, known as restriction sites. These enzymes act like molecular scissors, creating fragments of DNA with specific ends.   **3. Amplification of Gene of Interest Using PCR:** - Polymerase Chain Reaction (PCR) is a technique used to amplify specific DNA sequences. It involves multiple cycles of heating and cooling to replicate the target DNA. This allows scientists to obtain large quantities of the desired gene.   **4. Insertion of Recombinant DNA into Host:** - The amplified gene of interest is inserted into a vector, such as a plasmid or a virus. The vector carries the gene into a host cell, often a bacterium. This process is called transformation. **5. Obtaining the Foreign Gene Product:** - The host cell, now containing the recombinant DNA, replicates and expresses the foreign gene. This results in the production of the desired protein or other product encoded by the gene. **Applications of Recombinant DNA Technology** **Advantages of Recombinant technology** - Provide substantial quantity - No need for natural or organic factors - Tailor made product that you can control - Unlimited utilizations - Resistant to natural inhibitors **Disadvantages of Recombinant technology** - Effects natural immune system of the body - Can destroy natural ecosystem that relies on organic cycle - Prone to cause mutation that could have harmful effects - Concerns of creating super‐human race **ETHICAL ISSUES** - Ethical issues that arise from modern biotechnologies include the availability and use of privileged information, potential for ecological harm, access to new drugs and treatments, and the idea of interfering with nature - Biotechnology is playing an important role for the improvement of human life. These issues include many defects and side effect of products, tools and techniques along with economic, environmental loss and other negative impact. **Five (5) issues are categorized** - Socio-economic issues - Cultural issues - Legal issues - Environmental issues - Religious issues **Socio economic issues** - Scientific community and socio promise significant advancement in biotechnology but never yours the harmless regarding socio-economic life. - Socio- economic issues interfere with the natural way or the initial God's process of learning the environment. Issues could be related to the cultural backgrounds and also it could be on the level of different public awareness. The development of technology destroys the environment, which is a thricky thing **Cultural issues** - Different culture have different though and values. These values are the reflection of their long-lasting concept. - Biotechnology has given us everything to improve the quality of life. - The culture aspect of the human, there can be ethical issues arising from such matters **Legal issues** - Legal issues are being arises in the use of bilogical techniques - Particularly modern techniques such as stem cell technology, gene theraphy and human genome project have generated many issues in the society and there is need to resolve them for the satisfaction of the person who is recieving treatment or getting benefit from these techniques - Special laws protect many plants and animals. These lawsprotect these animals and plants from bieng distrubed to overcome. **Environmental issues** - Ecological issues might arise when one destroys the living flora and fauna. Gene manipulation of different crops to produce hybrids is one of the most prolematic issues.Even for most biotech experiments, other ornganism are made to sacrifice. Example: Surgarcane have gone through genetic mutation and recombination, which has continously destroyed the orginal constituent of the crop. **Religious issues** - One of the most faced issues with biotechnology is that it hurts people's sentiments on a religous basis. - Some holy plants and animals are blessed and very sacred to lots of communities. These communities protect the organism at any cause. Killing these organism is a matter of deep concern. Example: Cow is considered to be very sacred by hindus. People pray for the animals in countries such as india. **Learning Assessment** No activities just read and understand the modules and PPTs for the upcoming Final Exam **References** - **Additional Resources:**