Table of contents

1. Introduction to Genetics51m
2. Mendel's Laws of Inheritance3h 37m
3. Extensions to Mendelian Inheritance2h 41m
4. Genetic Mapping and Linkage2h 28m
5. Genetics of Bacteria and Viruses1h 21m
6. Chromosomal Variation1h 48m
7. DNA and Chromosome Structure56m
8. DNA Replication1h 10m
9. Mitosis and Meiosis1h 34m
10. Transcription1h 0m
11. Translation58m
12. Gene Regulation in Prokaryotes1h 19m
13. Gene Regulation in Eukaryotes44m
14. Genetic Control of Development44m
15. Genomes and Genomics1h 50m
16. Transposable Elements47m
17. Mutation, Repair, and Recombination1h 6m
18. Molecular Genetic Tools19m
- Genetic Cloning
  9m
- Methods for Analyzing DNA
  9m
19. Cancer Genetics29m
- Overview of Cancer
  21m
- Cancer Mutations
  7m
20. Quantitative Genetics1h 26m
21. Population Genetics50m
- Hardy Weinberg
  19m
- Allelic Frequency Changes
  31m
22. Evolutionary Genetics29m

15. Genomes and Genomics

Sequencing the Genome

Genetics

15. Genomes and Genomics

Sequencing the Genome

Previous problemNext problem

0:39 minutes

Problem 25b

Textbook Question

Whole-exome sequencing (WES) is helping physicians diagnose a genetic condition that has defied diagnosis by traditional means. The implication here is that exons in the nuclear genome are sequenced in the hopes that, by comparison with the genomes of nonaffected individuals, a diagnosis might be revealed.
If you were ordering WES for a patient, would you also include an analysis of the patient's mitochondrial genome?

Verified step by step guidance

Understand the purpose of Whole-Exome Sequencing (WES): WES focuses on sequencing the exons, which are the protein-coding regions of the nuclear genome. These regions are often where mutations causing genetic conditions are found.

Consider the role of the mitochondrial genome: The mitochondrial genome is separate from the nuclear genome and contains genes essential for mitochondrial function. Mutations in the mitochondrial genome can lead to mitochondrial disorders, which may not be detected by WES.

Evaluate the patient's symptoms: If the patient exhibits symptoms consistent with mitochondrial disorders (e.g., issues with energy production, muscle weakness, or neurological symptoms), it would be prudent to include an analysis of the mitochondrial genome.

Assess the diagnostic value: Including the mitochondrial genome analysis could provide additional insights, especially if the nuclear genome analysis does not reveal a clear diagnosis. This is because some genetic conditions are linked to mitochondrial DNA mutations.

Decide based on clinical context: The decision to include mitochondrial genome analysis should be based on the patient's clinical presentation, family history, and the likelihood of mitochondrial involvement in the condition being investigated.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

39s

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Whole-Exome Sequencing (WES)

Whole-exome sequencing (WES) is a genomic technique that focuses on sequencing all the protein-coding regions, or exons, of the genome. These exons represent about 1-2% of the entire genome but contain the majority of known disease-related variants. WES is particularly useful for diagnosing genetic disorders that are difficult to identify through traditional methods, as it allows for a comprehensive analysis of the genes that are most likely to be involved in disease.

Mitochondrial Genome

The mitochondrial genome is the genetic material found in mitochondria, the energy-producing organelles in cells. Unlike nuclear DNA, which is inherited from both parents, mitochondrial DNA is maternally inherited and is crucial for cellular energy metabolism. Analyzing the mitochondrial genome can be important in diagnosing certain genetic conditions, especially those related to energy production and metabolic disorders, which may not be captured by WES alone.

Comparative Genomics

Comparative genomics involves comparing the genomic data of affected individuals with that of nonaffected individuals to identify genetic variations associated with diseases. This approach helps in pinpointing mutations that may contribute to a genetic condition. By integrating findings from both nuclear and mitochondrial genomes, clinicians can gain a more comprehensive understanding of a patient's genetic makeup, potentially leading to more accurate diagnoses and treatment options.

Watch next

Master Sequencing Overview with a bite sized video explanation from Kylia

Start learning

Related Videos

Related Practice

Textbook Question

You have sequenced a 100-kb region of the Bacillus anthracis genome (the bacterium that causes anthrax) and a 100-kb region from the Gorilla gorilla genome. What differences and similarities might you expect to see in the annotation of the sequences, for example, in the number of genes, gene structure, regulatory sequences, and repetitive DNA?

321

views

Textbook Question

You have just obtained 100 kb of genomic sequence from an as-yet-unsequenced mammalian genome. What are three methods you might use to identify potential genes in the 100 kb? What are the advantages and limitations of each method?

558

views

Textbook Question

When comparing genes from two sequenced genomes, how does one determine whether two genes are orthologous? What pitfalls arise when one or both of the genomes are not sequenced?

458

views

Textbook Question

What is a reference genome? How can it be used to survey genetic variation within a species?

537

views

Textbook Question

Whole-exome sequencing (WES) is helping physicians diagnose a genetic condition that has defied diagnosis by traditional means. The implication here is that exons in the nuclear genome are sequenced in the hopes that, by comparison with the genomes of nonaffected individuals, a diagnosis might be revealed.

What are the strengths and weaknesses of this approach?

417

views

Textbook Question

Recall that when the HGP was completed, more than 40 percent of the genes identified had unknown functions. The PANTHER database provides access to comprehensive and current functional assignments for human genes (and genes from other species).

Go to http://www.pantherdb.org/data/. In the frame on the left side of the screen locate the 'Quick links' and use the 'Whole genome function views' link to a view of a pie chart of current functional classes for human genes. Mouse over the pie chart to answer these questions. What percentage of human genes encode transcription factors? Cytoskeletal proteins? Transmembrane receptor regulatory/adaptor proteins?

561

views

Textbook Question

Describe how enhancer screens can be used to uncover genetic redundancy.

475

views

Multiple Choice

Restriction enzymes are proteins responsible for what?