Edwards syndrome, also known as trisomy 18, is a rare genetic condition that occurs when a person has an extra copy of chromosome 18 in their cells. This condition can cause a number of serious health problems and often results in limited physical and mental development. Next, we will explore in detail the causes, symptoms and types of this genetic disease.
Causes of Edwards Syndrome
Edwards syndrome Edwards is caused by the presence of extra genetic material on chromosome 18. Normally, each cell in the human body contains 23 pairs of chromosomes, including two chromosomes of the 18th pair. However, in people with trisomy 18, one copy is produced extra copy of chromosome 18, resulting in a total of three copies instead of two.
This extra copy of genetic material can occur in two different ways:
Complete trisomy 18:
In most cases (about 95%), trisomy 18 results from the presence of a complete extra copy of chromosome 18 in all of the body's cells. This form of trisomy 18 is usually caused by an error in cell division during fertilization, known as nondisjunction, which results in the formation of an egg or sperm with an extra copy of chromosome 18. When this egg or sperm fuses with another during conception, the resulting embryo has three copies of chromosome 18 instead of two.
Translocation:
In a small percentage of trisomy 18 cases (approximately 5% ), the condition is caused by a genetic translocation. In this case, a portion of chromosome 18 attaches to another chromosome, usually chromosome 14. Although the total number of chromosomes is normal in these cases, the extra genetic material on chromosome 14 can cause developmental problems similar to those seen in complete trisomy 18.
Symptoms of Edwards Syndrome
Edwards syndrome is characterized by a wide range of symptoms that can affect different systems of the body. Some of the most common signs and symptoms of this condition include:
Physical:
- Low birth weight
- Prenatal growth retardation
- Cleft lip or palate
- Small hands and feet with overlapping fingers
- Congenital heart defects
Neurological:
- Delayed motor and cognitive development
- Strabismus
- Seizures
Respiratory:
- Respiratory problems, including sleep apnea
Gastrointestinal:
- Umbilical or inguinal hernias
- Problems in the gastrointestinal tract
It is important to note that the severity and combination of symptoms can vary significantly among people with trisomy 18. Some babies may have milder symptoms and have a longer life expectancy, while others They can experience serious complications from birth that affect their survival.
Types of Edwards Syndrome
There are several different forms of trisomy 18, which can be classified according to the severity of the condition and the origin of the extra copy of chromosome 18. Some of the most common types of Edwards syndrome include:
Complete Edwards syndrome:
In this type of trisomy 18, all the cells of the body contain a complete extra copy of chromosome 18. This form of the disease is often associated with a greater number of medical complications and a poorer prognosis compared to other forms of the condition.
Mosaic Edwards syndrome :
Mosaic trisomy 18 occurs when only some cells in the body have an extra copy of chromosome 18, while the rest of the cells have the normal chromosome configuration. This variant of the condition can present a wide variety of symptoms and its severity will depend on the proportion of cells affected.
Partial Edwards syndrome:
In the case of partial trisomy 18 , only a part of chromosome 18 is triplicated, rather than the entire chromosome. This can lead to symptoms and complications that vary depending on the location and size of the extra piece of genetic material.
Translocation Edwards syndrome:
This type of trisomy 18 is It occurs when a portion of chromosome 18 is attached to another chromosome (usually 14) instead of a complete extra copy of chromosome 18. The symptoms and severity of the condition will depend on the impact of the additional genetic material on the recipient chromosome.
Conclusions
Edwards syndrome, or trisomy 18, is a genetic condition that can have a significant impact on the health and development of affected people. The presence of an extra copy of chromosome 18 leads to a series of medical complications that can vary in severity and affect different body systems.
It is essential that people with this condition receive early diagnosis and medical care. specialized to optimize your quality of life and proactively address potential complications. Emotional support and appropriate counseling are also essential to help families cope with the challenges associated with Edwards syndrome.
Continuing research into this genetic disease and advances in treatment and management Care of those affected can contribute to improving the prognosis and quality of life of those with trisomy 18. Awareness of Edwards syndrome is also essential to promote understanding and empathy towards people with this condition and their families.