20.6 - Genome Projects

Question 1

What is the aim of genome sequencing projects?

Answer 1

The aim is to map the DNA base sequences that make up the genes of an organism and then map these genes onto the individual chromosomes of that organism, obtaining a complete map of all the genetic material (the genome) in that organism

Question 2

How many base pairs and genes does the human genome consist of?

Answer 2

The human genome consists of over 3 billion base pairs organized into around 20,000 genes.

Question 3

What is bioinformatics and why is it crucial for genome sequencing?

Answer 3

• Bioinformatics is the science of collecting and analyzing complex biological data such as genetic codes.
• It uses computers to read, store, and organize biological data rapidly and employs algorithms to analyze and interpret this data

Question 4

What technique is used to determine the complete DNA base sequence of an organism?

Answer 4

• Whole-genome shotgun (WGS) sequencing
• involves cutting DNA into small and easily sequenced sections, and then using computer algorithms to align overlapping segments to assemble the entire genome

Question 5

What has made genome sequencing faster and more efficient?

Answer 5

• Continuous updates to sequencing methods
• increased automation of the processes have made genome sequencing extremely rapid.

Question 6

What are SNPs, and why are they significant?

Answer 6

• single nucleotide polymorphisms are single-base variations in the genome associated with disease and other disorders.
• Over 1.4 million SNPs have been found in the human genome
• It allows for the quick identification of potential medical problems through screening and early intervention, and it aids in understanding evolutionary links between species.

Question 7

What is the proteome?

Answer 7

• The proteome consists of all the proteins produced by the genome, but more specifically, all the proteins produced in a given type of cell (cellular proteome) or organism (complete proteome) at a given time, under specified conditions.
• this is because only certain proteins are produced if the genes are turned on

Question 8

Why is determining the proteome of prokaryotes easier than that of eukaryotes?

Answer 8

• the vast majority of prokaryotes have just one, circular piece of DNA that is not associated with histones
• there are none of the non-coding portions of DNA which are typical of eukaryotic cells

Question 9

What is a practical application of understanding bacterial proteomes?

Answer 9

• Identifying proteins that act as antigens on human pathogens’ surfaces can aid in vaccine development and calculate dosages
• In response to the antigen, memory cells are produced which trigger a secondary response when the antigen is encountered on a second occasion

Question 10

Give an example of practical application of understanding bacterial proteomes to create vaccines

Answer 10

• Plasmodium falciparum causes malaria
• Plasmodium falciparum has 5,300 genes on 14 chromosomes which have been sequenced
• gives us an insight into its metabolism and knowledge of the proteins it produces —> important for developing vaccines

Question 11

What are the challenges in determining the proteome of complex organisms like humans?

Answer 11

• the presence of many non-coding genes and regulatory genes, with only about 1.5% of human genes coding for proteins
• individual variability in DNA sequences.

Question 12

What is the Human Proteome Project?

Answer 12

a project aimed at identifying all the proteins produced by humans.

Question 13

What are the genome features of Haemophilus influenza?

Answer 13

• Haemophilus influenza was the first bacterium to have its genome sequenced in 1995.
• It contains 1,700 genes comprising 1.8 million bases.

Question 14

What is the Human Microbiome Project?

Answer 14

A project sequencing the genomes of thousands of prokaryotic and single-celled eukaryotic organisms to help cure diseases and discover genes useful for applications like pollution cleanup and biofuel manufacturing.

Question 15

Distinguish between a genome and a proteome

Answer 15

A genome is all the genetic material in an organism. A proteome is all the proteins produced by the genome.

Question 16

Explain why determining the proteome of simple organisms like bacteria is easier than determining the proteome of complex ones like humans.

Answer 16

• Simple organisms generally have just one, circular piece of DNA that is not associated with histones and there is little, if any, non-coding DNA.
• Complex organisms have considerably more DNA and the majority of this does not code for proteins

Question 17

Explain how knowledge of the proteome of a pathogen might help to control the disease it causes.

Answer 17

It allows identification of those proteins that act as antigens on the surfaces of the pathogens. These antigens can then be used to produce effective vaccines against the disease.