GENETICS
cod. 00451

Academic year 2024/25
2° year of course - Second semester
Professor
Riccardo PAPA
Academic discipline
Genetica (BIO/18)
Field
Discipline biologiche
Type of training activity
Characterising
48 hours
of face-to-face activities
6 credits
hub: PARMA
course unit
in ITALIAN

Learning objectives

Students attending the course will acquire knowledge related to the transmission of genetic information in both eukaryotic and prokaryotic cells by integrating fundamental principles governing heredity with the molecular aspects defining genetic mechanisms. The methodological tool is the critical analysis of experiments that have led to the understanding of genetic mechanisms and their role in these scientific acquisitions.

Through course attendance and individual study, students will gain knowledge of formal genetics as well as the molecular nature of hereditary material, its replication, expression, and mutation.

By working through a series of examples and applied problems during the practical component of the course, students will be able to apply the knowledge acquired and evaluate their understanding. The final exam will assess their ability to learn the topics covered and communicate the knowledge acquired.

Prerequisites

None

Course unit content

The course is divided into two parts:

1. FORMAL GENETICS

Mitosis and Meiosis: Understanding cell division processes.
Mendelian Inheritance: The principles of heredity as discovered by Gregor Mendel.
Segregation of Traits: How traits are distributed among offspring.
Independent Assortment: How different genes independently separate from one another when reproductive cells develop.
Modification of Mendelian Ratios:
Co-dominance
Multiple Alleles
Lethal Alleles
Gene Interaction
Sex-Linked Inheritance
Chromosomal Theory of Inheritance: The theory that chromosomes are the carriers of genetic material.
Linkage and Recombination: How genes close to each other on a chromosome tend to be inherited together and how they can be recombined.
Crossing-Over: The exchange of genetic material between homologous chromosomes during meiosis.
Recombination in Yeast: The process of genetic recombination in yeast.
Transmission of Hereditary Traits in Prokaryotes:
Transformation
Conjugation
Transduction

2. MOLECULAR BASES OF HEREDITY

Experiments for the Identification of DNA as Genetic Material: Historical experiments that established DNA as the material of inheritance.
DNA Structure and Replication: The molecular structure of DNA and how it replicates.
Chromosome Structure and Organization in Prokaryotes and Eukaryotes: How chromosomes are structured and organized differently in prokaryotic and eukaryotic cells.
RNA Structure, Transcription, and Translation: The structure of RNA and the processes of transcription and translation.
The Genetic Code:
Characteristics and Deciphering of the Genetic Code
Gene Structure Organization:
Interrupted Genes
The "One Gene, One Enzyme" Theory
Construction of Metabolic Pathways
Genetic Complementation
Gene Expression: How genes are expressed in cells.
Variation in Chromosome Number and Structure: Changes in the number and structure of chromosomes and their consequences.
Gene Mutations:
Consequences of Mutations at the Gene Product Level
Reversion and Suppression
Isolation of Mutants
Spontaneous and Induced Mutants
Regulation of Gene Expression:
Transcriptional Regulation in Prokaryotes
The Lac Operon: Negative and Positive Control

Full programme

Course Content Overview
Transmission of Traits

Mitosis and Meiosis:
Mitosis: The process of cell division that results in two identical daughter cells.
Meiosis: The specialized form of cell division that produces gametes with half the number of chromosomes.

Mendelian Inheritance:
Segregation of Traits: How alleles separate during gamete formation and recombine during fertilization.
Independent Assortment: The principle that genes for different traits can segregate independently during the formation of gametes.
Multiple Alleles: The existence of more than two alleles for a single gene (e.g., ABO blood group system).
Lethal Alleles: Alleles that cause the death of an organism when present in a homozygous state.
Gene Interaction: How different genes can affect the expression of each other (e.g., epistasis).

Sex-Linked Inheritance:
Sex-Linked Traits: Traits associated with genes located on sex chromosomes (e.g., color blindness).

Chromosomal Theory of Inheritance:
Chromosomal Theory: The idea that chromosomes carry genetic information and are the basis for Mendelian inheritance.

Gene Linkage:
Gene Linkage: The tendency of genes located close to each other on the same chromosome to be inherited together.

Eukaryotic Gene Mapping:
Three-Point Mapping in Drosophila: A method for determining the relative positions of genes on a chromosome.

Transmission of Traits in Prokaryotes

Conjugation:
Conjugation: A process where genetic material is transferred between bacterial cells through direct contact.

Transformation:
Transformation: The uptake of free DNA from the environment by a bacterial cell.

Transduction:
Transduction: The transfer of genetic material from one bacterium to another via a bacteriophage.

Nature of Hereditary Material

Identification of Genetic Material:
Experiments: Historical experiments that demonstrated DNA as the genetic material (e.g., Griffith's experiment, Hershey-Chase experiment).

DNA Structure and Replication:
Structure: The double-helix structure of DNA.
Replication: The process by which DNA is copied before cell division.

Chromosome Structure and Organization:
Prokaryotes vs. Eukaryotes:
Prokaryotes: Circular DNA in a nucleoid region.
Eukaryotes: Linear DNA packaged into chromosomes within the nucleus.

RNA: Structure, Transcription, and Translation:
Structure: RNA’s single-stranded nature and nucleotides.
Transcription: The process of synthesizing RNA from a DNA template.
Translation: The synthesis of proteins based on RNA sequences.

The Genetic Code:
Characteristics: Universal, redundant, and unambiguous.
Deciphering: The process of translating RNA sequences into amino acids.

Gene Structure and Function

Gene Structure:
Organization: Exons, introns, promoters, and regulatory elements.
Interrupted Genes: Genes with non-coding regions (introns) interspersed with coding regions (exons).

One Gene-One Enzyme Hypothesis:
Hypothesis: Each gene encodes a specific enzyme that affects a particular metabolic pathway.

Gene Complementation:
Complementation: The concept that two different genetic mutations can be combined to restore a functional gene product.

Gene Expression:
Gene Regulation: The mechanisms controlling the rate of gene expression.

Changes in Genome Structure

Chromosome Number and Structure Variation:
Variations: Changes in the number of chromosomes (e.g., aneuploidy) or structural changes (e.g., deletions, duplications).

Gene Mutations:
Causes: Errors during DNA replication, environmental factors, or genetic changes.

Consequences of Mutations:
Effects: Changes in the gene product, which can be beneficial, neutral, or harmful.

Reversion and Suppression:
Reversion: A mutation that restores the original sequence.
Suppression: A second mutation that compensates for the effects of the first mutation.

Isolation of Mutants and Selection Systems:
Mutants: Identifying organisms with mutations.
Selection Systems: Techniques to isolate and identify mutants (e.g., antibiotic resistance).

Spontaneous and Induced Mutants:
Spontaneous: Mutations that occur naturally.
Induced: Mutations caused by external factors (e.g., chemical mutagens).

Regulation of Gene Expression

Transcriptional Regulation in Prokaryotes:
Prokaryotic Regulation: Mechanisms like operons to control gene expression (e.g., Lac operon).

Lac Operon: Negative and Positive Control:
Lac Operon: A model system for understanding gene regulation with both repressor (negative) and activator (positive) controls.

Trp Operon: Repression and Attenuation:
Trp Operon: A model for how gene expression is regulated in response to tryptophan levels.

Retroinhibition:
Retroinhibition: A feedback mechanism where the end product of a pathway inhibits an earlier step in the pathway.

Bibliography

Snustad DP, Simmons MJ (2014)
Principi di Genetica
5a Edizione
EdiSES

Binelli, Ghisotti (2018)
Genetica
EdiSES

Griffiths AJF, Wessler SR, Carroll SB, Doebley J (2013)
Genetica
7a Edizione
Zanichelli Ed

Teaching methods

The course will be conducted through lectures on the specific topics of the program, using PowerPoint presentations. The projected teaching materials will be made available on the Elly.

Assessment methods and criteria

The examination method during the course will include written tests consisting of multiple-choice questions, true/false questions, open-ended questions, and fill-in-the-blank questions.

Other information

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