The diseases genetic are conditions or disorders that are caused by alteration of the genome (set of genes) contained in the chromosomes. For instance: cystic fibrosis, Down syndrome.
They are diseases that may or may not be transmitted from generation to generation. To be inherited, the gene with the alteration must be in the ovules or sperm of the germ line and not in the somatic cells (the rest of the cells of the body).
It is estimated that there are more than 6000 genetic diseases and all of them with very different symptoms and treatments.
The causes of genetic diseases are:
- Mutation of one or more genes. It occurs when one or more genes change or vary, affecting the proper functioning of proteins. Often the mutation is influenced by environmental issues (eg exposure to radiation), in other cases, the mutated gene can be inherited or defective without intervention of the environment around the subject.
- Chromosome disorders. It occurs when there is a change in the number of chromosomes or when a part of a chromosome is missing, this can happen accidentally in the formation of the fetus or due to environmental causes.
- Genes inherited from parents. It occurs when an individual inherits altered genes from their parents, in this case, the disease is genetic and hereditary.
Examples of genetic diseases
- Cystic fibrosis. Genetic and hereditary disease that is produced by the mutation in the gene that generates the CFTR protein, responsible for controlling the secretion of certain fluids in the body. People with this disease do not produce this protein so they generate thick and sticky mucus that obstructs airways such as the respiratory and digestive tract. It is a disease that is only transmitted when both parents have a gene and the most common symptoms are: difficulty breathing, lung infections, and digestive and reproductive problems.
- Huntington’s disease or chorea. Disease caused by a genetic mutation on chromosome 4, which causes neuronal degeneration. If one of the parents suffers from this disease, the child will have a 50% chance of suffering from it. Symptoms appear between the ages of 30 and 40 and the most frequent are: motor disorders, such as movements without voluntary control, difficulty in maintaining balance and walking; cognitive and psychiatric disorders such as changeable behavior, cognitive loss, decreased ability to speak, and memory loss.
- Down’s Syndrome. Genetic disease produced by the duplication of one of the pairs that occurs on chromosome 21, which causes intellectual delay and variations in appearance and physical development. The characteristics vary according to each case, the most common are: cognitive impairment, late development and typical physical characteristics such as flexibility, flattened face and bulging eyes.
- Duchenne muscular dystrophy. Genetic disease that is a type of muscular dystrophy produced by mutations in the dystrophin gene (protein) which causes the weakness and atrophy of muscle mass. It is a disease that usually becomes visible from the age of 6, affects mainly males and is characterized by its rapid development.
- Sickle cell anemia. Genetic disease that is a type of anemia caused by variations in hemoglobin, which causes the red blood cells not to have the traditional shape (oval), but a shape similar to that of a crescent. This deformation hinders the movement of oxygen through the body and also its shape causes the red blood cells to die early, which generates anemia. The most common symptoms are shortness of breath, fatigue, swollen fingers, and infections.
- Celiac disease. It is a disease that appears in genetically disposed individuals that affects the digestive system. One of the most notable characteristics is the intolerance to gluten, present in wheat, oats, barley and rye, which generates inflammation and hinders the absorption of nutrients. If the person does not stop consuming gluten-based products, they will suffer from dehydration (due to diarrhea) and malnutrition. Celiac disease manifests itself in different ways according to each patient, among the most representative symptoms are: heartburn, diarrhea, indigestion, weight loss, skin rash and itching.
- Becker muscular dystrophy. Genetic disease that is a type of muscular dystrophy produced by mutations in the dystrophin gene (protein), which causes weakness and atrophy of muscle mass affecting the pelvis and legs. Although it has features similar to Duchenne muscular dystrophy, its symptoms are usually milder or appear more slowly. Men have a greater genetic predisposition to this disease than women and its most common symptoms are: loss of muscle mass, fatigue, loss of balance and difficulty walking.
- Achondroplasia. A group of genetic diseases caused by a genetic mutation that prevents normal bone growth. It is one of the main causes of dwarfism and can be both hereditary and not. People with this disease usually have an average size torso, but short limbs and a larger head. Among the symptoms that can be suffered are: apneas, back pain, curvature of the lumbar area and bowed legs.
- Noonan syndrome. Genetic disease produced by the mutation of several types of genes that affect the physical development of both boys and girls. Many of its symptoms are visible and among the most common are: skeletal alterations, short stature, facial characteristics such as wide-set eyes and a flat nose.
- Thalassemia. Genetic blood disease that occurs when there is a low presence of hemoglobin (a protein that is responsible for the transport of oxygen in the blood). There are different types so their intensity and symptoms vary, some of the most common are: anemia, chronic fatigue, general tiredness, paleness, shortness of breath and dizziness.