Medical Biology and Genetics Lecture Notes 2024 PDF

KOCAELİ HEALTH AND TECHNOLOGY UNIVERSITY FACULTY OF PHARMACY (ENGLISH) MEDICAL BIOLOGY and GENETICS Lecture-2 Introduction Assist. Prof. Dr. Seval ÇINAR [email protected] 2024  Introduction to...

KOCAELİ HEALTH AND TECHNOLOGY UNIVERSITY FACULTY OF PHARMACY (ENGLISH) MEDICAL BIOLOGY and GENETICS Lecture-2 Introduction Assist. Prof. Dr. Seval ÇINAR [email protected] 2024  Introduction to Medical Biology ang Genetics Introduction History Developments and Fundamentals Some Terms and Basic Concepts  Introduction Genetics: Branch of biology focusing on heredity and variation in living organisms Medical biology: Study of human health and disease at cellular and molecular levels →The study of biological principles applied to medicine →Bridges basic biology with clinical practice Key Areas of Medical Biology 1. Genetics and Genomics The development of medical biology has 2. Cell Biology experienced the process from macrocosmic view 3. Microbiology to microcosmic view: 4. Immunology anatomy ➔ histology ➔ cytobiology ➔ molecular 5. Molecular Biology biology➔ genetics ➔ structural biology 6. Pathology 7. Pharmacology 8. Clinical Research  Development of medical biology and genetics →Ancient and Medieval Medicine Hippocratic Medicine (circa 460-370 BC): Hippocrates is often regarded as the "Father of Medicine." He promoted the idea that diseases were caused by natural factors rather than supernatural ones. Hippocrates Galenic Medicine (circa 130-200 AD): Galen's teachings dominated medical practice for centuries, emphasizing anatomy, physiology, and the humoral theory, which linked bodily fluids to health. Aristotle (384-322 BCE): Early ideas on heredity and embryology Galen →Ancient Knowledge of Genetics Pre-modern Understanding: Ancient civilizations had some understanding of heredity, although they lacked the scientific framework to explain it. Practices such as selective breeding of plants and animals were common.  Ancient Foundations →Early Observations: Ancient Egyptians, Greeks, and Chinese documented their findings in scrolls, papyri… →Anatomical Studies: As scientific understanding advanced, researchers like Hippocrates and Galen conducted extensive anatomical studies, dissecting and documenting the structures of the human body. Early anatomical knowledge was based on observation and dissection of animals and humans. The Edwin Smith Papyrus (circa 1600 BCE) is one of the oldest known medical texts, containing descriptions of anatomical observations and surgical procedures. The ancient Greeks, such as Hippocrates (460-370 BCE) and Galen (129-216 CE), made significant contributions to anatomy, including the discovery of the circulatory system and the brain's function *Ancient medical instruments, Epypt  The Renaissance (14th century to the 17th century) →Emerging Theories: The Middle Ages and Renaissance periods saw the emergence of new theories and models, and the work of pioneering anatomists like Vesalius. →Anatomical Advances: Andreas Vesalius (1514-1564) published "De humani corporis fabrica," which corrected many of Galen's anatomical errors. →Introduction of Empirical Observation: The shift from theory-based medicine to observation and experimentation laid the groundwork for modern scientific methods. Andreas Vesalius The 17th to 19th Centuries Microscopy: The invention of the microscope allowed for the discovery of cells and microorganisms, leading to a better understanding of disease. Germ Theory of Disease: In the mid-1800s, scientists like Louis Pasteur and Robert Koch established the germ theory, demonstrating that specific microbes cause specific diseases. This fundamentally changed approaches to hygiene, sterilization, and infection control.  The first microscope. A drawing by Robert Hooke (1644). Published in Micrographia in 1655. This drawing is the first description of a microorganism. Antonie van Leeuwenhoek is widely known as the "Father of Microbiology".  Louis Pasteur's discoveries: Fermentation, Pasteurization, Rabies vaccine, disproved the theory of spontaneous generation with his swan-neck flask experiment. Spontaneous generation is an old failed theory that life could spontaneously emerge from non-living matter Robert Koch discovered the specific causative bacteria of deadly infectious diseases such as tuberculosis, cholera and anthrax. He is considered one of the main founders of modern bacteriology. He is also popularly known as the 'father of microbiology' along with Pasteur and is also referred to as the 'father of medical bacteriology'. 19th Gregor Mendel (1822–1884): Often referred Century to as the "father of genetics," Mendel conducted experiments with pea plants in the late 1850s and early 1860s. He discovered the basic laws of inheritance, including the concepts of dominant and recessive traits. His work went unrecognized during his lifetime but later became foundational for the field.  Mendel was an Austrian monk and biologist who loved to work with plants. By breeding the pea plants he was growing in the monastery's garden, he discovered the principles that rule heredity. In one of most classic examples, Mendel combined a purebred yellow- seeded plant with a purebred green-seeded plant, and he got only yellow seeds. He called the yellow-colored trait the dominant one, because it was expressed in all the new seeds. Then he let the new yellow-seeded hybrid plants self-fertilize. And in this second generation, he got both yellow and green seeds, which meant the green trait had been hidden by the dominant yellow. He called this hidden trait the recessive trait.  The Cell Theory (1830s) Matthias Schleiden and Theodor Schwann proposed: 1. All living organisms are composed of cells 2. The cell is the basic unit of life 3. All cells arise from pre-existing cells Laid foundation for modern cell biology and genetics The Birth of Modern Medical Biology (Late 19th to Early 20th Century) →Vaccination and Immunology: Edward Jenner's smallpox vaccine in 1796 marked the beginning of immunology, leading to the development of many vaccines that have saved millions of lives. Unvaccinated vs Vaccinated - Surviving a Smallpox Epidemic →Antibiotics: The discovery of penicillin by Alexander Fleming in 1928 revolutionized the treatment of bacterial infections. He isolated and studied the antibiotic substance penicillin from the mold Penicillium notatum in 1928  Griffiths Transformation Experiment (1928) The Griffith Experiment, conducted by Frederick Griffith, is a landmark study in microbiology that provided early evidence for the concept of genetic transformation. It involved two strains of the bacterium Streptococcus pneumoniae, one pathogenic (disease-causing) and the other non-pathogenic (harmless). 1.Bacterial Strains: Conclusion 1. Smooth strain (S strain): This strain Griffith concluded that some "transforming principle" from has a smooth polysaccharide the heat-killed S strain was taken up by the live R strain, capsule, making it virulent and transforming it into a virulent form. capable of causing disease. 2. Rough strain (R strain): This strain This experiment provided foundational evidence for the idea lacks the capsule, making it non- that genetic material could be transferred between pathogenic and unable to cause different bacterial strains. disease. The Griffith Experiment is often cited as a crucial step in 2.Procedure: understanding heredity and transformation, leading to the 1. Griffith injected mice with different field of genetics as we know it today. combinations of the bacterial strains: 1. Mice injected with the S strain died. 2. Mice injected with the R strain survived. 3. Mice injected with heat-killed S strain also survived. 4. Mice injected with a mixture of live R strain and heat-killed S strain died. 3.Observation: 1. Mice that received the mixture of live R strain and heat-killed S strain developed pneumonia and died. 2. Upon examination, Griffith found living S strain bacteria in the blood of these mice. The Birth of Modern Medical Biology (Late 19th to Early 20th Century) →Molecular Biology Foundations: The discovery of DNA as the hereditary material (Avery, MacLeod, and McCarty, 1944) The Discovery of DNA Structure (1953): James Watson, Francis Crick, Rosalind Franklin, and Maurice Wilkins Double helix structure of DNA revealed Explained mechanism for genetic information storage and replication Revolutionized understanding of heredity and gene function James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin Central Dogma of Molecular Biology (1958) Proposed by Francis Crick Describes flow of genetic information: DNA → RNA → Protein Central dogma: The concept that genetic information flows from DNA to RNA to proteins. Early 20th Century Chromosome Theory of Inheritance: In the Eleanor Carothers, was the first to early 1900s, researchers like Thomas Hunt provide physical evidence Morgan, Theodor Boveri made crucial discoveries supporting the theory. about the role of chromosomes in heredity. The identification of the behavior of Walter Sutton and Theodor Boveri developed the chromosomes during cell division Chromosomal Theory of Inheritance, which (mitosis and meiosis) provided a states that chromosomes carry the unit of heredity physical basis for Mendel's laws. In Vitro Fertilization (IVF) (1978) First "test-tube baby" born: Louise Brown Revolutionized treatment of infertility Opened doors for embryo research and genetic screening  Polymerase Chain Reaction (PCR) (1983) Developed by Kary Mullis Allows rapid amplification of specific DNA sequences Essential tool in molecular biology, forensics, and diagnostics  Advancements in the 20th Century →Medical Imaging: The development of X-rays, CT (computed tomography) scans, and MRIs (magnetic resonance imaging) allowed for non-invasive examination of internal structures, improving diagnosis and treatment planning. The Genomic Era (Late 20th Century) →Recombinant DNA Technology: The development of techniques to manipulate DNA in the 1970s (such as plasmid cloning and the polymerase chain reaction, PCR) revolutionized biotechnology and led to advances in medicine, agriculture, and industry. Paul Berg, Stanley Cohen, and Herbert Boyer Allowed manipulation of DNA sequences Led to production of synthetic insulin and other therapeutic proteins Foundation for genetic engineering and biotechnology →Human Genome Project (1990-2003): This monumental project mapped all the genes in the human genome, advancing our understanding of genetics, inheritance, and disease. International scientific research project Goal: Determine the sequence of the human genome Identified approximately 20,500-25,000 genes in human DNA Revolutionized genomics and personalized medicine Dolly the Sheep: First Cloned Mammal (1996) Created by Ian Wilmut and colleagues First mammal cloned from an adult somatic cell Sparked ethical debates and research into stem cells and regenerative medicine RNA Interference (RNAi) Discovery (1998) Andrew Fire and Craig Mello Mechanism for gene silencing using double-stranded RNA Important tool in functional genomics and potential therapeutic applications RNA interference (RNAi) is a biological mechanism where RNA molecules silence targeted genes, playing a critical role in regulating gene expression and defending against viral infections. Induced Pluripotent Stem Cells (iPSCs) (2006) Shinya Yamanaka reprogrammed adult cells into stem cells Opened new avenues for regenerative medicine and disease modeling Reduced ethical concerns associated with embryonic stem cells COVID-19 mRNA Vaccines (2020) Rapid development of mRNA vaccines against SARS-CoV-2 Demonstrated potential of mRNA technology in vaccine development Current Trends and Future Directions →Genomics and Personalized Medicine: Advances in sequencing technologies have allowed for rapid and cost-effective genome sequencing, leading to personalized medicine approaches that consider an individual's genetic makeup in treatment plans. →CRISPR-Cas9 Gene Editing (2012): In recent years, the development of CRISPR-Cas9 technology has enabled precise editing of the genome, opening up possibilities for gene therapy and the treatment of genetic disorders. →Regenerative Medicine: Stem cell research and tissue engineering hold the promise of regenerating damaged tissues and organs. →Biotechnology: The intersection of biology and technology continues to yield innovations in diagnostics, therapeutics (like mRNA vaccines), and medical devices. →AI and Big Data: The integration of artificial intelligence and big data analytics in healthcare is transforming research, diagnostics, and patient care, enabling more informed and efficient medical decisions.  Fundamentals 1. The Building Blocks of Life Cells: The fundamental units of all living organisms Biomolecules: Proteins, nucleic acids, lipids, and carbohydrates Genetic Material: DNA and RNA, the infromation carriers 2. Principles of Genetics Gene Expression: How genes dictate the characteristics of organisms Mutations: Heritable changes in the genetic code Inheritance: How traits are passed down through generations 3. Cellular Processes Cell Cycles and Cell Division : Mitosis and meiosis, ensuring growth and reproduction Metabolism: Influenced by both genetic and environmental factors Signaling: Using genetic information to guide drug treatment Cell renewal, Cell Death  4. Genetics and Disease →Human Genetics and Chromosomal Abnormalities Mutation based disorders: Caused by mutations in a single gene Multifactorial Disorders:Influenced by both genetic and environmental factors