GENETICS Chapter 1 – General introductions Examples Hemophilia is the genetic defect in human when blood clothing is deficient leading to the spontaneous bleeding. Gene for Fix and Fviii are located on chromosome X There are more than 1300 alteration in the Fviii gene, many of them cause Haemophilla from mild to severe states. Novel mutation in Fviii gene cause Haemophillia A deletion Nissenetal.BMCHematology (2018) 18:17 Family transmission of haemophillia among European Royal families http://sciencecases.lib.buffalo.edu/cs/files/hemo.pdf What is Genetics? Science studies:genes, genetic variation and heredity in organisms The importance of genetics ⚫ Demonstrate the roles of genes and how they affect organism’s life and health ⚫ Started with domestication, now genetics has contributed to the improvement of plants and animals by engineering and propagation. ⚫ Genetics also plays role in pharmaceutical industry where drugs, food additives and bio-products are genetically produced from bacteria, fungi… to make them efficient producers in industry. ⚫ Understanding in genetics helps physicians recognize many gene disorders… that finally lead to the development of therapies… Division of genetics ⚫ Transmission genetics – study how traits are passed from one generation to the next. ⚫ Molecular genetics – study the chemical nature of gene and gene products. ⚫ Population genetics – study the genetic composition of the group of individuals from the same species. Transmission Molecular genetics genetics Population genetics The rise of science of genetics ❖ Domestication and agriculture recorded the first understanding of genetics ⚫ Selection of the good trait for next crop ⚫ Many plants and animals were products of domestication: wheat, pea, lentil, barley, dog, goat, sheep. ⚫ Many products were produced by simple crossing making them more variable. ⚫ The future of genetics ⚫ ……… http://margreetdeheer.com/eng/science.html ❖ The early written records ⚫ Hemophilia inherited through mother ⚫ Human reproduction through pangenesis hypothesis ⚫ The rise of modern genetics ⚫ The discovery of cell under simple microscope by Robert Hook (1653-1703) ⚫ Nehemiah Grew (1641–1712) reported that plants re- produce sexually by using pollen from the male sex cells ⚫ Gregor Mendel (1822–1884) discovered the basic principles of heredity ⚫ Matthis Jacob Schleiden (1804–1881) and Theodor Schwann (1810–1882) proposed the concept of the cell theory in 1839 ⚫ ⚫ Charles Darwin (1809 – 1882) put forth the theory of evolution through natural selection and published his ideas in On the Origin of Species in 1856 ⚫ WalterFlemming(1843 – 1905) observed the division of chromosomes in 1879 and published a superb description of mitosis ⚫ The twentieth-century genetics ⚫ Walter Sutton (1877–1916) proposed in 1902 that genes are located on chromosomes. ⚫ Thomas Hunt Morgan (1866 – 1945) discovered the first genetic mutant of fruit flies in 1910 and used fruit flies to unravel many details of transmission genetics ⚫ James Watson (b. 1928) and Francis Crick (b. 1916) described the three-dimensional structure of DNA in 1953, ushering in the era of molecular genetics. The fundamental concepts of genetics ⚫ Cells are of two basic types: eukaryotic and prokaryotic. Prokaryotic cells lack a nuclear membrane and posses no membrane-bounded cell organelles, whereas eukaryotic cell are more complex, possessing a nucleus and membrane-bounded organeles. ⚫ The gene is the fundamental unit of heredity. Gene is the unit of information that encodes a genetic characteristics ⚫ Genes come in multiple forms called alleles. A gene that specifies a characteristic may exist in multiple forms called alleles ⚫ Genes confer phenotypes: genes code for the traits, along with the environmental factors, determine phenotypes. Genes are inherited but not the phenotype. ⚫ Genetic information is carried in DNA and RNA. ⚫ Genes are located on chromosomes. ⚫ Chromosomes are separated through the process of mitosis and meiosis. ⚫ Genetic information is transferred from DNA to RNA to protein ⚫ Mutations are permanent, heritable changes in genetic information ⚫ Some traits are affected by multiple factors. The human height is affected by 17 regions in genome (by genome wide screening). ⚫ Evolution is genetic change General introduction Cell reproductions – asm1 Basic principles of inheritance – Mendel inheritance Extension of Mendel inheritance Linked gene inheritance – asm2 Genetic material /chromosome structure and variation From gene to protein – DNA replication and transcription From gene to protein – RNA processing – asm3 1. 2. 3. 4. 5. 6. 7. 8. ▪ 9. 10. 11. 12. 13. 14. Midterm exam From gene to protein – genetic code and translation. Regulation of gene expression. Recombinant DNA technology, mutation and genomic – asm4 Organelle DNA Quantitative genetics 1 Each section takes 3 hrs Quantitative genetics 2 Additional information for the course ⚫ Attendance (80% of the class hour) is required for attending final exam ⚫ Assignment: from quiz, homework, test … ⚫ Grading: ⚫ Midterm: 30% ⚫ Lab: 15% (refer to the lab requirement for this section) ⚫ Assignment: 15% ⚫ Marks from the highest 3 out of 5 quizzes are taken as assignment ⚫ Final exam: 40% ⚫ Bonus will be assigned during the course for your performance References ⚫ Textbook ⚫ Genetics: A Conceptual Approach, 2008, Pierce, B.A, 3rd Edition. W.H. Freeman and Comp., New York, 730 pp. ⚫ Supporting books ⚫ Genetics: Analysis & Principles, 2009, Brooker, R.J., 3rd Edition. McGraw-Hill, New York, 844pp. ⚫ Genetics: From Genes to Genomes, 2004, Hartwell, L.H., Hood, L., Goldberg, M.L., Reynolds, A.E., Silver, L.M. & Veres, R.C., 2nd Edition. McGraw-Hill, NY. 865 pp.
