Despite our differences, we human beings share at least 99.99% of the genome. Simply put, we all differ by a mere 0.1 percent of genes. These are the genes that trigger the difference between two individuals in how we appear, grow, and develop.
Over 80 percent of rare diseases in the human body are caused by a genetic mutation. The mutation in the minuscule difference between two differences is the cause of undiagnosed diseases that affect about 8% of our population.
Whole-exome sequencing genetic tests helps us in overcoming the challenge of identifying such rare diseases. The promising new technique provides a holistic outlook on coding genetic variation.
What is the Whole Exome Sequencing Genetic Test?
Whole Exome Sequencing (WES) is dynamic and one of the most comprehensive genetic tests. It is used to identify any diseases causing changes in genes in the body.
Exons are coding sections of an RNA transcript, or the DNA encoding it, from which most of the protein in the human body is coded from. Therefore, a functional protein may be altered when any exon of a gene changes.
About 1.7 percent of the human genome encoding proteins comprise exons. Compared to the genome, the exome is quite smaller and only has information about all coding regions. The majority of disease-causing mutations happen in the exon. Though the exome constitutes only 1 percent of the genome, 85 percent of all disease-causing mutations are located there.
In the whole-exome sequencing genetic test, the protein-coding regions of all genes of the human genome are sequenced with the help of next-generation sequencing technologies (NGS). Whole-exome sequencing is a powerful method to detect the molecular basis of genetic disorders across multiple medical specialties.
Compared to the traditional gene diagnostic methods, the diagnostic yield of whole-exome sequencing is relatively higher. Depending on the medical specialty, with severe, early-onset disorders, a definite diagnosis is always obtained in 20 to 60 percent of cases.
When an index patient and parents or other first-level family members use whole-exome sequencing genetic tests to determine the diagnosis, the chances of accurately predicting the diseases are intensified.
Benefits of Whole Exome Sequencing Compared to Single Sequencing
Whole exome sequencing is used for individuals with multiple symptoms at the same time. Therefore, it makes it difficult for doctors to pinpoint the exact gene responsible for the disease.
WHS offers a fast, reliable and cost-effective, quick solution involving the sequencing of the entire coding region of the genome. As the exome represents only a small part of the DNA in the whole genome, the testing labs can sequence it quickly. This results in potentially faster and quicker results. A fast process helps in preventing the delay of diagnosis. Any delayed diagnosis can have a dramatic impact on the quality of a patient’s life. When the results come quickly, it relatively impacts various treatment and management decisions.
Furthermore, the Whole Exome Test Cost in India is reasonable compared to the cost in western countries.
Whole Exome Sequencing tests are most suitable for individuals with
- a complex, rare genetic disorder with multiple differential diagnoses.
- a genetically heterogeneous disorder.
- a specified genetic disorder where a particular genetic test is not available.
- Unsuccessful previous genetic testing.
The limitations
Though, there are certain limitations in genome areas where we know less. For example, there are some disease-causing variants outside the exome which haven’t been studied. These elements can include anything from minor changes in DNA regions that regulate gene activity to broad-scale changes known as structural variations. These can also be the alterations that change the folding structure of chromosomes.
Where You can get Whole Exome Sequencing
Many genetic labs or molecular diagnostics labs offer whole-exome sequencing tests to make a difference in patients’ lives. The labs help in discovering and assessing the person’s risk of developing a genetic disease. These diagnostics labs are a great source for guided treatment decisions and assessing disease progression and recurrence risk. The Whole Exome Sequencing Cost is also reasonable compared to other companies in western countries.
It is easy to book a whole-exome sequencing test. You can book the best online or ask for a sample collection from the comfort of your home.
