The 10 most common inheritable diseases - medical - 2023



Hereditary or inheritable diseases are the set of conditions and disorders whose occurrence is encoded in the genesIn other words, they are not caused by pathogens or by alterations that occur throughout life.

Therefore, having the gene that codes for this disease is a "sentence" of suffering from it. Regardless of leading healthy lifestyle habits, the disorder will inevitably appear.

Another characteristic of these diseases is that, as their name suggests, they are inherited. These disease-causing genes are passed from parent to child, causing the disorder to persist through generations.

In this article we will see the 10 most common inherited diseases, observing its symptoms and therapies to reduce its signs, since it must be taken into account that, since they are encoded in our genes, there is no cure for these disorders.

Is genetic disease the same as hereditary disease?

Despite being closely related, no. They are not synonymous. Broadly speaking, we could summarize it in that all hereditary diseases are genetic, but not all genetic diseases are hereditary.

A genetic disease is any disorder that appears because the person has an "error" in their genetic material, an alteration that results in both anatomical and physiological problems. Most of the time, these gene mutations appear suddenly during the early stages of embryonic development, causing the person to suffer from this disease for life.

However, we speak of hereditary disease only when these genetic alterations also affect germ cells, that is to say, to the ovules and the sperm. If these cells are encoded for the disease, when the individual reproduces, they will pass on the altered gene to their children.

Therefore, a genetic disease is only inherited when the gene that codes for the disorder is also present in the eggs and sperm, which act as a "transmitter" of the disease.

Thus, for example, Down syndrome is a genetic disorder since its appearance is determined by an alteration of the genetic material, but most of the time it is not hereditary, since the germ cells do not transmit the information that codes for the syndrome.

What are the most common inherited diseases?

In this article we will present some of the most common diseases that are transmitted from generation to generation and that are encoded in the genetic material, so there is no possible prevention. Regardless of lifestyle and other factors, if the person has the genetic "mistake," they will suffer from the disease.

In addition, beyond "receiving it from the parents", there is no other cause. Too It must be borne in mind that they cannot be cured, as there is no possible way to reverse genetic alterations.

Therefore, for these diseases we can only analyze the symptoms and possible therapies that reduce the impact of the genetic disorder suffered by the person and that they have inherited from their parents.

1. Cystic fibrosis

Cystic fibrosis is an inherited disease that affects the functionality of the lungs, although it also damages the digestive system and other organs of the body. Due to a genetic error, the mucous membranes of those affected are thicker and stickier than normal, causing that, instead of lubricating the ducts, they accumulate in the lungs and other regions.

Symptoms depend on how much mucosa production is affected, and may improve or worsen over time. The main symptoms are due to obstruction of the airways due to sticky mucus and are as follows:

  • Short of breath
  • Persistent cough
  • Mucus
  • Wheezing when breathing
  • Frequent lung infections
  • Nasal congestion
  • Very salty sweat
  • Difficulty exercising
  • Intestinal obstructions
  • Growing problems
  • Constipation

The diagnosis is made during the first month of life through a blood test, where the presence of a substance released by the pancreas is determined. Once the disease is confirmed, treatment begins as soon as possible.

It cannot be cured, but drug therapies, physical therapy and rehabilitation sessions allow those affected to see relief from symptoms and reduce the risk of complications.

2. Phenylketonuria

Phenylketonuria is an inherited disease characterized by a genetic error that causes those affected not to have an enzyme that degrades phenylalanine, an amino acid present in protein foods. This causes phenylalanine to accumulate in the body, causing different damages.

Those affected usually have fair skin and blue eyes, since melanin, which is the pigment responsible for darkening the skin and hair, cannot be formed if phenylalanine is not degraded. The accumulation of this amino acid causes the following symptoms:

  • Rashes
  • Developmental delay
  • Behavior problems
  • Neurological disorders
  • Strange odor on skin, breath, and urine
  • Microcephaly (small head)
  • Hyperactivity
  • Intellectual disability
  • Psychological disorders

The only effective treatment consists of prevention, since it is necessary to avoid the accumulation of this amino acid, since it cannot be degraded and it will accumulate indefinitely, causing more and more serious problems. Therefore, the only way to reduce symptoms is to eat a diet very low in protein for life (avoid milk, meat, fish, eggs, legumes ...). If we do not introduce the amino acid, it will not accumulate.

3. Hemophilia A

Hemophilia A is an inherited disease characterized by a genetic error that makes the person unable to clot the blood well, so when faced with bleeding, it is very difficult to stop it.

The most common symptoms are the following:

  • Nasal bleeding
  • Blood in urine and stools
  • Prolonged bleeding from wounds
  • Swelling in joints
  • Bleeding with no apparent cause
  • Bruising

The treatment consists of a replacement therapy for the damaged “blood clotting factor”, a molecule responsible for clotting the blood and that those who suffer from this disease do not have due to genetic alteration. Therefore, the person will be administered concentrates of this molecule to relieve symptoms and avoid complications.

4. Fragile X syndrome

Fragile X syndrome is an inherited disease in which, due to an error on the X chromosome, the affected person does not have a specific gene. This gene is responsible for producing an essential protein for proper brain development. For this reason, fragile X syndrome is associated with intellectual disability.

Brain involvement can be more or less severe, although the symptoms are usually as follows:

  • Learning problems
  • Intellectual disability (which can be serious)
  • Trouble socializing
  • Violent behaviors (in some cases)
  • Emotional disturbances
  • Speech difficulties

Obviously, this disease has no cure. However, educational and behavioral therapy and medicines can help those affected have a better quality of life.

5. Sickle cell anemia

Sickle cell anemia is an inherited disease characterized by changes in the anatomy of red blood cells, the cells responsible for transporting oxygen through the body through the blood. Those affected have red blood cells that are too rigid and in the wrong shape, so oxygen transport does not take place as it should.

This lack of healthy red blood cells and the consequent problems in oxygen transport has the following symptoms:

  • Fatigue and weakness
  • Pain in the abdomen, chest, joints and bones (from blocked blood flow)
  • Swelling of the hands and feet
  • Recurrent infections
  • Vision problems
  • Stunted growth

Despite no cure, drug-based treatments to reduce pain and relieve symptoms can help. Blood transfusions and even a bone marrow transplant can also be done.

6. Duchenne muscular dystrophy

Duchenne muscular dystrophy is an inherited disease characterized by a mistake in a gene, a condition that causes not enough protein to be produced to keep muscles healthy.

This causes a progressive loss of muscle mass that causes the following symptoms:

  • Trouble walking
  • Muscle pain
  • Rigidity
  • Learning difficulty
  • Frequent falls
  • Motor problems
  • Soft spot

Despite no cure, drug treatments and physical therapy sessions help slow the progress of the disease and relieve symptoms.

7. Huntington's disease

Huntington's disease is an inherited disease characterized by progressive deterioration of neurons in the brain.

Symptoms vary greatly depending on the person, although as a general rule the most frequent symptoms are the following:

  • Learning difficulty
  • Impulsiveness
  • Promiscuity
  • Insomnia
  • Weakness and fatigue
  • Irritability and sadness
  • Muscular stiffness
  • Involuntary movements

Despite the absence of a cure, medications can alleviate and reduce the impact of the psychiatric and motor manifestations of the disease.

8. Marfan syndrome

Marfan syndrome is an inherited disease that affects connective tissue, that is, the integrity of cartilage, adipose, bone and lymphoid tissue, in addition to the tendons. The affected person will therefore have problems with the heart, blood vessels, bones and eyes, among others.

The main symptoms of the disease are as follows:

  • Tall slim build
  • Nearsightedness (which can be severe)
  • Scoliosis (curved spine)
  • Flat feet
  • Heart murmurs (blood flows too fast through the heart)
  • Crowded teeth

Although there is no cure, we do have treatments that are focused on reducing the possibility of developing complications, which can be serious.

9. Hemochromatosis

Hemochromatosis is an inherited disease in which those affected absorb more iron than they should from what is eaten. This causes an excess of iron in the body, which begins to accumulate in the heart, liver and pancreas.

This accumulation of iron causes the following symptoms:

  • Weakness and fatigue
  • Joint pain
  • Abdominal pain
  • Diabetes

However, over time, the disease progresses and serious symptoms such as heart and liver failure begin to appear, which, along with diabetes, are life-threatening.

Despite the absence of a cure, treatments, based on periodic blood draws to restore iron levels, are useful to alleviate symptoms and prevent serious complications from appearing.

10. Achondroplasia

Achondroplasia is an inherited disease characterized by impaired bone development, causing the most common type of dwarfism.

The most common symptoms of a person affected by achondroplasia are the following:

  • Short stature
  • Narrowing of the spine
  • Short arms and legs
  • Arched feet
  • Low muscle tone
  • Prominent forehead
  • Large head compared to the rest of the body

Obviously, there is no cure and the treatments can only be focused on solving some problems of the spine so that the affected person does not develop complications.

Bibliographic references

  • Castaño, L., Bilbao, J.R. (1997) "Introduction to Molecular Biology and application to Pediatrics: Concepts of genetics in hereditary diseases". Spanish Annals of Pediatrics.
  • French Association against Myopathies (2005) "Genetic diseases and genetics of diseases". AFM.
  • Robitaille, J.M. (2016) "The Transmission of Hereditary Characteristics". SOFAD.