Genetics program (9CFU); Undergraduate Course of Biotechnology (L-2), 2022-2023
Professor: Pasquale Mosesso
1. Mendelian inheritance and chromosome theory of inheritance
Mendel’s postulates and elements of mendelian genetics applied to man and agriculture. Laws of probability and their relevance to explain genetic events (the product law and the sum law); Use of chi-square analysis to evaluate the influence of chance on genetic data, interpretation of chi-square calculations. Cell cycle; mitosis, meiosis and concordance between meiosis and genetic mendelism. Demonstration of chromosome theory of inheritance. Chromosomal sex-determining system; sex-limited and sex-influenced inheritance.
2. Extensions of mendelian genetics
Alleles alters phenotypes in different ways: Incomplete dominance, codominance, multiple alleles, lethal alleles. Environment and gene expression: Effects of “internal” and “external” environments. Penetrance and expressivity. Gene interaction. Epistasis and pleiotropy.
3. Genes linkage and chromosome mapping
The crossing -over. Linkage maps: Mapping with three-point crosses; Interference; Some examples of linkage maps; Chi-squared test.
4. Molecular structure and replication of genetic material
Molecular structure of DNA and RNA: Identification of DNA as genetic material (experiments of Hershey and Chase). Characteristics of nucleic acids (experiments of Chargaff). Replication of DNA in the prokaryotes and eukaryotes. Demonstration that reproduction of DNA is by semiconservative replication (experiments of Meselson e Stahl).
5. Genetic analysis in bacteria
The bacterial chromosome: Transfer of genetic material in bacteria: Transformation; Conjugation; sexduction and transduction. Methods of genetic mapping in bacteria and bacteriophages. Extrachromosomal elements: Natural and artificial plasmids.
6. Molecular properties of genes
Structure and function of genes: Components of the eukaryotic chromosomes (DNA, histonic and non-histonic protein); Chromatin structure and nucleosomes; Repetitive DNA sequences and DNA satellite; How genes work (hypothesis one gene one protein); colinearity between gene and protein. Complementation and mutation sites. Translation of mRNA; Structure and functions of tRNA. The genetic code; Studies by Nirenberg, Matthaei and Others led to the deciphering of the code; Early studies established the basic operational pattern of genetic code: The triplet nature of the code; the nonoverlapping nature of the code; the commaless and degenerate nature of the code.
7. Mechanisms of production of genetic variability
Definition and classification of mutations: Gene mutations: base pair substitutions, insertions, deletions; reversion and suppression of mutations; phenotypic effects of gene mutations. Fluctuation test and spontaneous mutation in bacteria (neo-Darwinian theory). Chromosome mutations: structural (chromosomal aberrations) and numerical (aneuploidy, polyploidy).
Environmental agents which damage DNA: Ionizing electromagnetic radiations (X-rays, gamma-rays, betatron-synchrotron radiations); Ionizing subatomic particles (alpha particles, beta particles neutrons). Non-ionizing electromagnetic radiations (UV-A, UV-B, UV-C); UV and ozone. Electromagnetic fields (microwaves, HF, ELF etc.). Chemical mutagens: alkylating agents; environmental pollutants in the cities [car exhaust, sulphur and nitrogen oxides, polycyclic aromatic hydrocarbons (PAH), formaldehyde, asbestos]; food additives and contaminant of aliments (aflatoxins, ochratoxins nitrosamines, heterocyclic aromatic amines, phenols of vegetal origin, etc); therapeutic agents (mitomycin-C, bleomycin, nitrogen mustards, inhibitors of DNA topoisomerases I and II, cytostatic agents); pesticides. Biological mutagens: microbial and viral pathogens; transposable elements.
DNA repair systems: fotoliase, alchiltransferases, “nucleotide excision repair” (NER), “base excision repair (BER), “mismatch repair” (MMR), “SOS” repair, recombinational repair: repair of DNA single strand breaks (SSB) and DNA double strand breaks (HR e NHEJR); DNA damage, activation of cellular “checkpoints.
Transposable elements: Bacterial and eukaryotic transposable elements; Retrovirus; Transposons and chromosome mutability.
8. Gene regulation and expression in bacteria
Negative and positive regulation; Genetic dissection of lac operon in E. coli; The operon of tryptophan.
9. Gene regulation and expression in eukaryotes
Gene expression regulation at epigenetic, transcriptional and post-transcriptional levels.
10. Principles of Genetic engineering
Basic techniques to manipulate genetic material (DNA and RNA): Restriction enzymes; Cloning of DNA fragments.
Chromosomal and plasmidico DNA separation and purification.
Techniques of analysis of DNA, RNA: Gel Electrophoresis; Amplification of nucleic acid fragments by Polymerase Chain Reaction; Hybridization, Southern Blotting, and Northern Blotting.
DNA sequencing methods: General principles of the procedure; sequencing of large genomic regions.
In vitro mutagenesis.
11. Population genetics analysis
Allele frequencies in populations vary in space and time. The Hardy-Weinberg law describes the relationship between allele frequencies and genotype frequencies in an ideal population. The Hardy-Weinberg law can be used in human populations for multiple alleles, X-linked traits and estimating heterozygote frequencies. Natural selection is a major force driving allele frequency change: Natural selection, fitness and selection, selection in natural populations. Mutation creates new alleles in a gene pool. Migration and gene flow can alter frequencies. Genetic drift causes random changes in allele frequencies in small populations. Non-random mating changes genotype frequency but not allele frequency: Inbreeding; genetic effects of inbreeding.

Recommended textbooks:

Peter J. Russel “Genetics: A Molecular Approach;

Griffiths A.J., Doebley J., Peichel C., Wassarman D.A. "Introduction to Genetic Analysis";

Griffiths A.J.F, Wessler S.R., Carrol S.B., and Doebley J. "Introduction to Genetic Analysis";