Using genome projects
Laura Armstrong & Joe Wolfensohn
Teachers
Recall Questions
This topic requires prior knowledge of the genome and proteome, as well as differences in eukaryotic and prokaryotic DNA. You can test your knowledge on these below.
What is meant by the term ‘genome’?
The complete set of genetic material (DNA) in an organism, including all its genes.
What is a proteome?
The full range of proteins that a cell or organism can produce.
Why is it easier to determine the proteome of prokaryotes than eukaryotes?
Prokaryotes have no introns or regulatory sequences in their DNA.
Topic Explainer Video
Check out this @JoeDoesBiology video that explains using genome projects or read the full notes below. Once you've gone through the whole note, try out the practice questions!
What are genome projects?
Genome projects aim to determine the entire base sequence of an organism’s DNA. One famous example is the Human Genome Project, which was completed in 2003. These projects allow scientists to:
- Identify the location and sequence of genes
- Understand the genetic basis of diseases
- Develop diagnostics, treatments, and vaccines
Over time, sequencing methods have become faster, cheaper, and automated.
Genome Sequencing and the Proteome
Simple Organisms (e.g. Bacteria)
In prokaryotes:
- There is little to no non-coding DNA
- Genes are usually not regulated and are all expressed
- No introns or complex splicing. Therefore, the genome directly determines the proteome
Key Application:
- Helps identify potential antigens (proteins on pathogen surfaces) for vaccine development
- e.g. Sequencing the genome of Neisseria meningitidis helped researchers identify surface proteins to use in the vaccine.
Complex Organisms (e.g. Humans)
In eukaryotes:
- Genes contain introns, other non-coding sequences between genes, and regulatory elements
- Genes may be turned on or off in different tissues or at different times
- Alternative splicing can create multiple proteins from one gene
So, even if the full genome is known, predicting the entire proteome is difficult
This limits the direct application of genome data to protein function or disease prediction in complex organisms.
Key Terms
- Genome: The complete set of DNA in an organism, including all of its genes.
- Proteome: The full range of proteins that a cell or organism can produce.
- Antigen: A molecule (often a protein) that triggers an immune response.
- Non-coding DNA: DNA that does not code for proteins, including introns and regulatory sequences.
No answer provided.
Exam Tip
When evaluating the usefulness of genome data:
- Always differentiate between prokaryotic and eukaryotic organisms.
- Emphasise that proteome prediction is accurate in bacteria, but not in humans due to non-coding DNA and gene regulation.
- For application questions, link sequencing to vaccine development by referencing antigen identification.
No answer provided.
Determining the genome of the viruses could allow scientists to develop a vaccine.
Explain how. (2 marks)
- The scientists could identify proteins (that derive from the genetic code)
OR
The scientists could identify the proteome
- They could then identify potential antigens to use in the vaccine
Practice Question 1
Try to answer the practice question from the TikTok on your own, then watch the video to see how well you did!
Practice Question 2
Try to answer the practice question from the TikTok on your own, then watch the video to see how well you did!