A cyst is a closed sac of tissue that can form in almost any part of the body. They may contain fluid, air, pus, or other materials. Cysts are common and often benign (not cancerous). While some cysts might cause pain or changes in appearance, many are asymptomatic and discovered incidentally during medical imaging.
When Cysts Have a Genetic Basis
While many cysts arise from non-genetic factors, some types are directly influenced by a person’s genetic makeup. This genetic connection can involve inherited mutations or new spontaneous genetic changes. These factors can disrupt normal cellular processes, leading to cyst formation.
Gene mutations affect protein production, impacting cell growth, fluid regulation, or tissue structural integrity. Faulty proteins might lead to abnormal cell growth or fluid imbalance, causing fluid accumulation. Understanding these mechanisms helps differentiate hereditary cysts from those with other causes.
Inherited Cystic Conditions
Several genetic conditions feature cysts. Polycystic Kidney Disease (PKD) is a common inherited disorder where fluid-filled cysts grow in the kidneys, potentially leading to kidney enlargement and reduced kidney function. Autosomal dominant polycystic kidney disease (ADPKD) is the most common form, typically manifesting between ages 30 and 40, requiring only one copy of an altered gene (PKD1 or PKD2) to be inherited. In contrast, autosomal recessive polycystic kidney disease (ARPKD) is rarer and more severe, often presenting in infancy or even in the womb, requiring two copies of the altered gene (PKHD1).
Von Hippel-Lindau (VHL) disease is another inherited condition characterized by tumors and cysts in various body parts, including the kidneys, pancreas, and central nervous system. VHL is inherited in an autosomal-dominant pattern; a single altered VHL gene copy is sufficient to increase the risk of developing these growths. Approximately 80% of individuals with VHL disease inherit the altered gene from an affected parent; about 20% result from new genetic mutations.
Cysts Without a Genetic Link
Many common cysts are not associated with genetic inheritance. They often arise from blockages, inflammation, injury, or normal bodily processes. Epidermoid cysts, sometimes called sebaceous cysts, result from blocked hair follicles or skin trauma, leading to keratin buildup under the skin.
Ganglion cysts are non-cancerous lumps that form near joints or tendons, most commonly on the wrist or hand. Their exact cause is not known, but they are thought to relate to repetitive microtrauma or connective tissue degeneration, causing fluid from a joint or tendon to collect. Baker’s cysts, or popliteal cysts, develop behind the knee due to knee joint problems, such as arthritis or meniscus tears, leading to excess synovial fluid production.
Most ovarian cysts are functional cysts, a normal part of the menstrual cycle and not genetic. These resolve on their own. Simple kidney cysts are also common, especially as people age, and are not inherited, though their exact cause is not fully understood.
Navigating Genetic Inheritance and Support
For individuals concerned about cysts, especially with a family history of cystic conditions, medical evaluation is a first step. Healthcare providers may recommend genetic testing to identify gene mutations associated with inherited cystic diseases. Genetic testing can help confirm diagnosis, predict disease progression, and inform family planning.
Genetic counseling offers support and information to individuals and families navigating these conditions. Counselors explain inheritance patterns, assess individual risks, and help interpret genetic test results. They also provide guidance on managing the condition and making informed decisions about health and family planning, helping individuals understand their genetic information.