Overview
Inherited diseases are conditions caused by changes in genes or chromosomes that are passed through families. These conditions can affect growth, metabolism, blood, muscles, nerves, organs, or many body systems at once. Some are present at birth, while others are noticed in childhood or adulthood. The severity can range from mild to life-threatening.
Key Symptoms
Symptoms depend on the specific disease. Possible signs include developmental delay, repeated infections, unusual bleeding, muscle weakness, seizures, vision or hearing loss, breathing problems, or poor growth. Some inherited conditions cause symptoms only later in life, such as heart, nerve, or movement problems. In some people, there may be no symptoms even though they carry a gene change.
Causes and Risk Factors
Inherited diseases happen when a gene or chromosome change affects how the body develops or functions. These changes may be passed down in different ways, such as dominant, recessive, X-linked, or mitochondrial inheritance. Risk may be higher if there is a family history of the condition, if both parents carry the same recessive gene change, or if a chromosome change happens during egg or sperm formation. Sometimes an inherited disease appears for the first time in a family because of a new genetic change.
Who Is Affected
Inherited diseases can affect people of any age, sex, ethnic background, or country. Some conditions are more common in certain populations because of shared ancestry or community marriage patterns. A person may be affected, may carry a gene change without symptoms, or may have a milder or more severe form than relatives with the same condition. Families with one known inherited disease may have questions about future pregnancies and testing for other relatives.
Prevention
Many inherited diseases cannot be prevented once the gene change is present. However, learning about family history, carrier screening, newborn screening, and genetic counseling may help people understand risks and options before or during pregnancy, or after a family member is diagnosed. In some conditions, early detection can reduce complications through close monitoring or supportive care. Public health screening programs differ by country.
Diagnosis and Tests
Diagnosis often begins with a medical history, family history, and physical examination. Tests may include blood tests, imaging, metabolic screening, chromosome analysis, or genetic testing. In some cases, testing may be offered before pregnancy, during pregnancy, after birth, or later in life when symptoms appear. Genetic counseling can help explain what test results may mean for the individual and family.
Treatment Categories
Treatment depends on the specific inherited disease and the body systems involved. Care may include medicines, surgery, physical or occupational therapy, nutrition support, hormone treatment, blood products, enzyme replacement, organ-specific care, or monitoring for complications. Some inherited conditions have targeted therapies, while others are managed mainly with supportive care. Care is often provided by a team that may include primary care clinicians, specialists, and genetic professionals.
Living With It
Living with an inherited disease can affect daily life, school, work, family planning, and mental health. Regular follow-up may be needed to monitor symptoms and prevent complications. Families may benefit from clear information about inheritance, support groups, rehabilitation services, and school or workplace accommodations when needed. Emotional support can be important for both affected people and relatives.
When to Seek Medical Care
Seek medical care if you or your child has unexplained developmental delay, repeated severe illness, unusual bleeding, seizures, muscle weakness, poor growth, or a strong family history of early deaths or serious unexplained disease. Medical advice is also important before pregnancy or early in pregnancy if there is a known inherited condition in the family. Ask about genetic counseling if a relative has been diagnosed with a hereditary disorder.
When It May Be an Emergency
Some inherited diseases can lead to emergencies, especially in babies and children. Get urgent medical help for trouble breathing, seizures, severe dehydration, sudden confusion, loss of consciousness, chest pain, stroke-like symptoms, or a baby who is very sleepy, feeding poorly, or difficult to wake. Emergency symptoms depend on the condition, so families may be given a specific action plan by their healthcare team.