Rare diseases present a unique challenge due to their low prevalence and the complexity of their diagnosis. Timely diagnosis is key to improving the quality of life of patients with rare diseases and facilitating the development of targeted therapies. For this reason, genetic tools have become an essential resource for diagnosing these conditions, enabling a more personalized and precise approach to patient care. On the occasion of Rare Disease Day, which will be celebrated on February 29, we want to highlight the importance of genetic diagnosis in improving the quality of life of patients with rare diseases and facilitating the development of targeted therapies.
What do we mean by rare diseases?
Rare diseases child A group of medical disorders that affect a minority of people compared to common illnesses. They are characterized by their diverse symptoms and signs, which can vary significantly from one disorder to another and even among patients with the same condition.
It is estimated that 72% of these diseases have a genetic origin, while others are due to infections, allergies, and environmental factors. Although child While uncommon, these diseases share common characteristics, as they are usually serious, debilitating, chronic, degenerative, and often life-threatening conditions. Furthermore, they tend to have an early onset, can affect an individual's independence, and cause a variety of chronic pain.
The definition of rare diseases differs in different regions of the world, depending on their demographics and healthcare systems. In Europe, a disease is considered rare when it affects fewer than 1 in 2,000 people, while in the United States, the criterion for identifying and classifying rare diseases is that the number of affected individuals must not exceed 200,000.
It should be noted that, although each rare disease individually may be rare, collectively these diseases affect a significant number of people worldwide. It is estimated that between 41% and 6% of the world's population lives with a rare disease, which equates to approximately 450 million people affected globally. This figure represents a significant number and has a considerable impact. impressive in the healthcare system and in medical research in common.
Main problems faced by those living with rare diseases
Lack of knowledge, difficulty accessing relevant information, and a scarcity of research centers and specialized centers for rare diseases make living with them challenging. ocean It's difficult for both patients and their families.
One of the greatest challenges for these patients is achieving an accurate and specific diagnosis of their disease. Sometimes, relatively common symptoms can mask underlying rare diseases, which can lead to misdiagnosis and a delay in starting treatment. It is estimated that in approximately 30% of cases, an early and accurate diagnosis could have prevented the disease from worsening. Therefore, it is of utmost importance to identify the specific pathology and initiate the appropriate treatment tailored to the patient's needs. blade to delay or even avoid complications in the symptoms and avoid unnecessary interventions.
Furthermore, living with a rare disease can have both an emotional and financial impact. Uncertainty, anxiety, depression, and stress are common. child common due to lack of information, difficult access to resources and the social stigma surrounding these diseases, among many other obstacles.
Diagnostic tools
Diagnosing rare diseases presents a significant challenge, as the patient's clinical picture cannot always be linked to a specific disease, making it difficult to find appropriate treatment.
Even so, diagnostic tools for rare diseases have made significant progress thanks to advances in genomics and next-generation sequencing technology. These tools child This is key to adapting the patient's medical management and addressing symptomatic issues early. Furthermore, when performed on newborns exhibiting signs and symptoms of rare diseases, it allows for determining the origin of the pathology and helps couples who wish to have more children.
The main techniques include:
Panels of qualities:
The panels of qualities child tools that simultaneously analyze a specific group of qualities that are known to be associated with a disease or group of diseases.
Whole exome sequencing (WES):
This technique focuses on sequencing all exons, that is, the protein-coding regions of the genome. WES can help identify mutations that cause diseases in qualities acquaintances.
Whole genome sequencing (WGS):
WGS involves the complete sequencing of an individual's entire genome. This technique is more comprehensive than WES and can detect changes in non-coding regions of the genome, which is useful for identifying mutations in regulatory regions or other genetic changes.
Exome and diagnostic genome
For rare diseases and complex clinical cases, exome sequencing and diagnostic whole-genome sequencing represent the most comprehensive tools available. In these cases, it is major to perform a clinical interpretation of the genetic variants according to the symptoms presented by the individual and thus arrive at the patient's diagnosis.
Exome or Genome Diagnosis child These are especially useful in cases where the patient presents with a complex clinical picture that does not correspond to any specific pathology and affects different organ systems. For this, it is essential to have the patient's complete medical history, which allows the specialist to objectively define the patient's HPOs and, based on them, the qualities to study. HPO stands for Human Phenotype Ontology and is used internationally to establish phenotypic abnormalities in human diseases.
It is estimated that in 85% of cases, the variants causing the disease are located in coding regions, so exome sequencing would be a valid approach in most cases. ban, the diagnostic performance of the genome is slightly prevalent to the diagnostic exome, being able to reach a yield of 40% depending on the pathology studied, because the genome analyzes non-coding regions.
Exome- and genome-based diagnostics at TRIO
Following this line of thought, both exome and genome diagnostics can benefit from the option of sequencing parental DNA, known as TRIO diagnostics.
This option facilitates the identification of variants possibly related to the disease and helps determine if childinherited or de novo from segregation studies commonplace. Together with the patient's clinical information, this tool allows for a more effective and accurate analysis of the possible causes of the disease, resulting in a significant improvement in the diagnostic process.
Diagnostic panels
In cases where the clinical picture presented by the patient ocean characteristic of a disease or group of diseases, it is possible to direct the study to the set of qualities These tests are called diagnostic panels and consist of whole-exome sequencing, but with an analysis focused on the qualities of interest. Some laboratories opt directly for sequencing the qualities required, which is a disadvantage, since with whole exome sequencing a reanalysis of the genomic data can be performed if no variant of interest is detected in the qualities analyzed.
Diagnostic panels typically focus on specific areas, such as neuromuscular disorders, cardiovascular disorders, or metabolic diseases, among others. Veritas offers a comprehensive portfolio of diagnostic panels, as well as the option for prescribing physicians to design their own. board genetic according to the patient's needs.
Considerations in the use of genetic diagnostic services
When sequencing techniques are used for diagnosis, the technology used for variant detection is important, but roughage other aspects to consider.
In cases where the patient presents with a rare disease and a complex clinical picture, a good interpretation of the variants found by experts in the field is vital To arrive at an accurate diagnosis, the quality and coverage of the genetic analyses performed must also be considered, as insufficient sequencing can affect the accuracy of the diagnosis.
Therefore, it is of imperative It is important to choose a diagnostic service that includes high-quality sequencing and an expert team in genetic counseling and interpretation, which is key to the diagnosis of rare diseases.
At Zogen, we perform genetic testing to prevent and improve the diagnosis of serious diseases such as cancer, heart disease, and other conditions, including a large number of rare diseases.
We offer a wide range of DNA tests to help you take care of your health proactively and improve your quality of life. We also support you throughout the process by providing consultations with specialists. Contact us.
Fountain: https://www.veritasint.com/blog/en/genetic-tools-for-diagnosis-of-rare-diseases/
