Hereditary diseases: nature, mechanisms of development and modern approaches to diagnosis
Hereditary diseases are diseases that are passed down from generation to generation through genetic material. They can affect the functioning of various organs and systems, manifesting themselves both in childhood and in adulthood. Some of them have a serious impact on a person's health, while others can remain hidden and manifest only under certain conditions.
What are hereditary diseases and why do they occur?
Hereditary diseases are based on changes in genes or chromosomes. These changes can be inherited from parents or arise spontaneously through mutations during fetal development. Mutations affect the structure or function of proteins, which can lead to disruptions in the functioning of cells and the body as a whole.
The development of hereditary diseases depends on the mechanism of transmission of genetic material. They can be:
- Autosomal dominant – if one mutated gene from one parent is enough to develop the disease (for example, Marfan syndrome).
- Autosomal recessive – if the disease manifests itself only in the presence of two copies of the mutated gene (for example, cystic fibrosis).
- Linked to the X chromosome – such pathologies are more common in men, since they have only one X chromosome (for example, hemophilia).
- Mitochondrial – are transmitted exclusively from the mother, since mitochondrial DNA is contained in the egg (for example, Leigh syndrome).
Classification of hereditary diseases
Depending on the mechanism of damage to the body, hereditary diseases are divided into several groups.
Molecular genetic disorders
These diseases arise from defects at the level of individual genes. They can affect protein metabolism, metabolism, or tissue structure.
- Phenylketonuria is a disorder of phenylalanine metabolism that leads to damage to the nervous system.
- Sickle cell anemia is a change in the structure of hemoglobin that makes it difficult for the blood to transport oxygen.
Chromosomal abnormalities
They arise due to changes in the number or structure of chromosomes. They can lead to serious congenital pathologies.
- Down syndrome – an extra copy of the 21st chromosome causes developmental delay and an increased risk of comorbidities.
- Turner syndrome – the absence of one X chromosome in women causes hormonal disorders and problems with reproductive function.
Polygenic hereditary diseases
They arise as a result of a combination of several mutations and environmental influences.
- Type 2 diabetes is associated with genetic predisposition and lifestyle.
- Arterial hypertension – has a hereditary basis, but is significantly influenced by eating habits and physical activity level.
Mitochondrial diseases
Associated with mutations in mitochondrial DNA that disrupt cellular energy balance.
- Mitochondrial myopathy – causes muscle weakness and nervous system dysfunction.
- Pearson syndrome is a complex disorder of hematopoiesis and pancreatic function.
Methods for diagnosing hereditary diseases
Modern medicine offers a wide range of methods for detecting genetic disorders before symptoms appear or even before the birth of a child.
Prenatal diagnosis
It is performed during pregnancy to identify genetic pathologies in the fetus.
- Amniocentesis is an analysis of amniotic fluid that allows for the examination of fetal DNA.
- Chorionic villus sampling is a test of placental cells to detect chromosomal abnormalities.
- Non-invasive DNA testing is a blood test of the mother to assess the genetic characteristics of the fetus.
Genetic testing adults and children
These tests help determine the presence of mutations in certain genes and assess the risk of developing hereditary diseases.
- The BRCA1 and BRCA2 test can identify the risk of developing breast cancer.
- Mutation carrier testing in couples planning a pregnancy helps prevent the transmission of serious genetic diseases.
Laboratory methods
- Polymerase chain reaction (PCR) is used to identify specific genetic mutations.
- Fluorescence in situ hybridization (FISH) helps detect chromosomal abnormalities.
- DNA sequencing methods are used to analyze large amounts of genetic data.
Modern approaches to the treatment of hereditary diseases
Today, medicine offers both symptomatic treatment methods and innovative approaches that allow for the correction of genetic disorders.
- Gene therapy – a method that involves introducing healthy copies of genes into the patient's cells.
- Replacement therapy – used in cases of deficiency of certain enzymes, as in the case of Gaucher disease.
- Cell therapy – uses stem cells to repair damaged tissues.
Thanks to advances in genetics, it has become possible not only to detect hereditary diseases, but also to effectively treat them. Regular genetic testing allows you to assess risks and take the necessary measures to maintain your health in a timely manner.
Highly qualified cytomorphologist with over 45 years of experience. For 33 years, she headed the cytology laboratory of the regional oncology clinic. Expert in early diagnosis of malignant neoplasms at Medi Lab Plus LLC. More details…