Genomics Fundamentals Quiz

Course Information

• Course Title: The Human Body
• Course Code: PJ1311
• Topic: Introduction to Genomics
• Presenter: Kandil

Lecture Content Outline

• Three lectures on Genomics
  • Introduction to Genomics
  • The central dogma of life (transcription, translation)
  • Cell cycle and control mechanisms

Introduction to Genomics

• Genomics is the study of the complete human genome (DNA), its structure, and how it functions.
• The genome is the entire set of DNA instructions, including 23 chromosome pairs within the cell nucleus, and a small chromosome within the cell's mitochondria.
• A genome contains all the information needed for an individual to develop and function.
• Genomics studies the genes in DNA, their functions, and their role in the body's growth, development, and operation.
• Genomics utilizes diverse methods to scrutinize the body's DNA and associated components.

Gene Structure

• Genes consist of DNA's specific nucleotide sequences.
• Some genes serve as blueprints for protein production.
• Many genes do not code for proteins.
• Chromosomes are thread-like structures that package DNA molecules.
• Every chromosome contains a tightly coiled DNA molecule, supported by proteins known as histones.
• The DNA within chromosomes is the blueprint for creating proteins.

Gene Structure - Introns and Exons

• Introns are non-coding regions that are removed during pre-mRNA processing.
• Exons are coding sequences that remain within mature mRNA.
• Introns are prevalent in eukaryotic precursor mRNA.
• In prokaryotes, introns are confined to tRNA and rRNA.

Why are Introns Important?

• Introns enable alternative splicing of exons – This means, multiple proteins can be synthesized from a single gene.
• Introns generate non-coding RNAs, which influence gene expression in various ways.
• Introns are involved in crucial regulatory mechanisms.
• The connection between introns, cancer, and their utility as tumor markers is also an ongoing area of research.

Types of Genomics

• Structural Genomics: Aims to ascertain the structure of every protein that is encoded by a genome.
• Functional Genomics: Collects and analyzes data from sequencing projects to understand gene and protein functions, genotype-phenotype interactions, as well as gene and protein relationships.
• Comparative Genomics: Compares genomic features across different species to better comprehend evolutionary relationships and gene functions across varied organisms.
• Mutational Genomics: Examines genome alterations, including mutations, to evaluate their impact on gene functionality.

History of Genomics

• Genomics emerged in the 1980s and gained significant momentum in the 1990s with initiating genome projects for several biological species.
• Important tools in genomic research include microarrays and bioinformatics.
• Molecular biology labs were instrumental in the advancement of genomics.
• Laboratory automation fuelled the production of substantial datasets.
• Bioinformatics emerged in response to the need to analyze, synthesize, and understand these genomic data.

The Human Genome Project

• Led by the National Institutes of Health (NIH) and the National Human Genome Research Institute.
• Produced a high-quality version of the human genome sequence and made it openly accessible in public databases.
• The human genome is exceptionally complex and vast.
• In the human genome, DNA stretches approximately 6 feet.
• It consists of about 30,000 to 40,000 genes.
• Launched in 1986 and was initially projected to last 15 years.
• Completed in 2003, two years ahead of schedule.

Human Genome Project Goals

• Identify the number of genes present in human DNA.
• Determine the sequence of the human genome's 3 billion base pairs.
• Develop databases to store genomic information.
• Advance tools for efficient data analysis.
• Transfer genome-related technologies to the private sector.
• Address ethical, legal, and social issues associated with the project.

Sequencing Strategies

• DNA must be amplified (increased in quantity) before sequencing.
• Cloning and Polymerase Chain Reaction(PCR) are common amplification methods,
• Sequencing techniques used in the HGP include Sanger and shotgun sequencing.

Sequencing Strategies: Sanger Method

• DNA fragments migrate through capillary tubes.
• Analyzing and identifying DNA fragments.
• Determining the order of bases using computer analysis.

Sequencing Strategies: Shotgun Method

• Genomic DNA is fragmented, the fragments are sequenced, and the fragments are assembled using overlapping regions.

Lessons from the Human Genome Project

• The Human Genome Project revealed a detailed blueprint of human DNA.
• Recognizing that the relationship between genes and observable traits is more complex than initially anticipated.
• The number of human genes is considerably fewer than originally estimated.
• The significance of non-coding regions is understood.

Why Sequence Genomes?

• Molecular Medicine: Enhancing disease diagnosis, preventing disease, detecting genetic predisposition, developing and applying treatments customized to a patient's genetic profile.
• Microbial Genomics: Quickly identify and treat pathogens (disease-causing microorganisms), and monitor and control harmful substances in environments.
• Risk Assessment: To quantify the potential health risks linked to specific elements, like radiation and harmful chemicals.
• DNA Identification for Forensics: To uncover suspects' identities, analyze crime scene evidence, and solve paternity cases.

The End of the Beginning

• The Y chromosome was the last missing piece of the human genome sequence.