The teaching is organized as follows:

Learning outcomes

To offer the basic knowledge of human biology in an evolutionary perspective, underlying the molecular and cellular processes shared by all living organisms. To encourage students to critically evaluate experimental data by illustrating prime experiments of the past and contemporary biology. To describe the following processes: duplication, transmission, expression of the hereditary information; how changes arise To describe the hierarchy of master genes involved in tooth development and their interactions. To offer an updated information about the recombinant DNA technology and its applications to dentistry To teach the genetic bases of inherited diseases and how to interpret their modes of transmission To illustrate in particular various genetic conditions affecting dental health. At the end of the course, students must demonstrate to have gotten acquainted with basic knowledge of cellular functions, cell reproduction, cell-cell interactions, organism-to –organism interactions and organisms-to-environment interactions. They must also demonstrate to know how genetic traits are transmitted (mendelian and post-mendelian genetics, population genetics). They should be able to recognize inheritance patterns of genetic disorders, in particular those involving teeth development and structure. All these notions are a pre-requisite for further in depth studies , which will be undertaken by the students in subsequent courses.

Program

Macromolecules common to living organisms: basic characteristics. Life’s origin: the chemical evolution hypothesis (Urey & & Miller experiment). The evolutionary theory proposed by Darwin. The modern vision of evolutionism. “Nothing in biology makes sense but in the light of evolution”. The evolution of human species. Model organisms in biology Three major groups of living organisms: Eubacteria, Archea, Eukarya. Main characteristics of Prokaryotes: cell structure, cell wall structure, genome, reproduction, habitats, interactions with other living organisms. Cyanobacteria: how they changed the terrestrial athmosphere. Evolution of eukaryotes, the endosymbiontic theory. Brief recall of organelles structure and functions (from the Citology module); roles and functions of the cell memebrane. From unicellular to multicellular eukaryotes. Cell communication, signal molecules. Cell growth and energetic metabolism in brief. Cell cycle and its regulation. Cell division (mitosis). The nucleus; DNA, chromatin, chromosomes. Cell death: apoptosis and necrosis. Ploidy and reproductive strategies; sexual reproduction. Meiosis and human gametogenesis. Nomal and pathological human karyotype. Methods of prenatal and post natal analysis . Cytogenetic anomalies and syndromes. Molecular biology: the historical experiments that led to the discovery of DNA as the genetic material (F.Miescher; Griffith, di Avery, McLeod e McCarty, Hershey e Chase) . The structure of the double helix (R.Franklin, M. Wilkins, J Watson & F Crick); DNA replication (Meselson & Stahl). Also RNA is an informational molecule (Fraenkel- Conrat).. DNA polymerase and DNA replication “in vivo”( in prokaryotes and eukaryotes) and “in vitro” (the PCR technique). Telomerase and telomeres replication. Denaturation, renaturation, hybridization of DNA molecules; molecular probes , applications (FISH). The informational flow: from DNA to proteins. A. Garrod’s studies, the “one gene-one enzyme hypothesis by Beedle & Tatum, the central dogma of molecular biology. Roles of various RNA species in the informational flow. Gene expression in prokaryotes, polycistronic RNAs, the operons. Gene transcription in eukaryotes, promoters, RNA polymerase II, RNA processing (splicing mechanism), alternative splicing and its evolutionary significance. mRNA translation, the genetic code, codons and anticodons, the “wobbling” theory. Protein synthesis in the eukaryotic cell post-translational modifications, protein sorting and secretion. The regulation of gene expression in eukaryotes. Chromatin structure and modifications. X chromosome inactivation in female somatic cells. DNA binding proteins which act as activators/repressors of transcription, DNA binding motives. The role of non-coding RNAs (nc-RNAs) The beta globin genes cluster: a paradigm of space/time regulation of gene expression Developmental biology. Master genes (e.g. the HOX selector genes) ; model organisms (Drosophila) Master genes which act in tooth development Cell reprogramming: from the beginning to nowadays (the experiments of Briggs, Wilmut and Dolly sheep, S. Yamanaka) Gene expression and sex determination (SRY and DAX1 genes). The human genome and its plasticity. Transposable elements, gene families, repeated sequences, pseudogenes. Genome evolution. Mutations: pre-adactativity ; mutations and selection, m. and fitness. Spontaneous mutations: how do they occur; induced mutations , types of mutagens , mode of action. DNA repair systems: Proof-read repair, MMR; DSB repair, BER, NER. Ames’ test for the identification of mutagens. Ionizing radiations, definition of LET and EBR. Somatic mutations and cancer: target genes in tumorigenesis (proto-oncogenes, oncosuppressor genes, DNA repair genes) The process of cell ageing: causes, consequences, antidotes. The recombinant DNA technology: principles, tools, applications. The production of therapeutic proteins. Transgenic animals: knock-out and knock-in mice. Genome editing Genetics. Mendel’s experiments. Allelic segregation , independent assortment. T. Morgan’s school: gene association and recombination. Genetic maps. Human genetics. Blood groups: ABO; Rh. Modes of inheritance: autosomal dominant/recessive, X linked. Various examples of inherited diseases; genetics of tooth anomalies and defects. Examples of pedigrees: how to interpret them correctly. Exceptions to Mendelism: a) cytoplasmic (mithocondrial) inheritance,; b) dynamic mutations; uniparental dysomies; Imprinted genes. Allelic and genotypic frequencies in populations. The Hardy Weinberg law: its conditions of validity, its exceptions How and when to apply it. DIDACTIC MODES Attendance to lessons is mandatory. Classes will consist of theorical lessons covering the whole exam program. Oral explanations will be coadiuvated by PowerPoint presentations and videos, which will be made available to students through a dedicated Department web site. Additional didactic supports (multiple choice quizzes for self-assessment, journal articles , reviews, etc.) may be suggested during the course and will be made available to students for download. During the whole Academic Year, students may request personal reception to the teachers, by e mail. -SUGGESTED TEXTBOOKS - Le basi della biologia (Cellula-Genetica-Evoluzione) H. Helena Curtis, et al., I edizione italiana, 2017 Zanichelli ed. Bologna, ISBN: 9788808768988 -Campbell Biologia e Genetica, Pearson Italia 2015; ISBN: 9788865189320

Bibliography

Examination Methods

Written test (25 multiple choice quizzes plus 5 open questions) concernin the entire program. Goals of the written test are: a) to monitor students’ learning process, b) to monitor students’ capacity of personal re-elaboration of notions, c) to monitor students’ ability to apply theoretical notions to experimental queries.
Score (in /30) of the written test strongly influences final outcome. A positive score will be achieved with at least 18 correct MCQ plus 1 open question. An oral examination may follow only if written text score is ≥ 18/30. Students can either retire from the examination or refuse the proposed score at any time. In both cases they shall enroll again for the whole examination (written and oral)