Genetics of Gaucher Disease: Genes, Inheritance, Effects on the Body, Symptoms, and Treatment

Gaucher disease is inherited, comes in several different types, and affects several of the body’s tissues and organs. This genetic disease affects about one in 50,000 to 100,000 people. The most common type is type one, and most often affects Ashkenazi Jewish people. The other types of this disease are relatively uncommon and do no affect Ashkenazi Jewish people more often. Understanding the genetics of Gaucher disease helps parents, and patients, better understand the disease and how it affects the body.

Inheritance and Genes

GBA gene mutations cause this disease. This gene is what gives the instructions responsible for creating the beta-glucocerebrosidase enzyme. This enzyme is responsible for breaking down glucocerebroside (a fatty substance) into ceramide (a simpler fat molecule) and glucose (sugar). Mutations in this gene eliminate or greatly reduce beta- glucocerebrosidase activity. When the amount of this enzyme is low, glucocerebroside and other associated substances can reach toxic levels by building up in the cells. Due to the unusual accumulation and deposits of these substances, organ and tissue damage results, leading to the characteristic features of this disease.

Gaucher disease takes the autosomal recessive pattern for inheritance. This means that in each cell, both gene copies have mutations. The parents of the person born with this condition, usually do not have any symptoms of signs, but both will have one copy of the gene that is mutated.

Types, Symptoms, and How Gaucher Disease Effects the Body

Type one is the most common type and is also referred to as non-neuronopathic Gaucher disease. Patients with this type’s central nervous system (spinal cord and brain) aren’t typically affected. The associated features, can present themselves anytime between childhood and adulthood and vary between mild to severe. Symptoms include enlargement of the spleen and liver, thrombocytopenia causing easy bruising, bone abnormalities (such as fractures, bone pain, and arthritis), anemia, and lung disease.

Types two and three affect the central nervous system so they are referred to as neuronopathic. Type two typically causes life-threatening issues that begin during infancy. Type three tends to have a slower progression. In addition to the symptoms experienced with type one, patients may also experience seizures, abnormal eye movements, and brain damage.

The perinatal lethal type is the most severe type. Those with this type can start to experience life-threatening complications during infancy, or even before birth. The characteristics and symptoms of this type are extensive swelling (due to the accumulation of fluids prior to birth), skin abnormalities, scaly and dry skin, distinctive facial features, hepatosplenomegaly, and serious neurological problems.

The cardiovascular type largely affects the heart, causing calcification of the heart valves. Patients may also experience eye abnormalities, mild splenomegaly, and bone disease.

Treating Gaucher Disease

Part of treatment involves understanding the genetics of Gaucher disease. Patients who have types one through three may be treated with enzyme replacement therapy, bone marrow transplantation, and medication (Zavesca).

This disease cannot be cured, but most types can be managed. Patients who do not develop signs and symptoms until they are adults, have relatively normal life expectancies. Those who develop signs and symptoms when they are infants, usually do not live longer than two years. Patients who have type three and live to be teenagers can often survive for several additional years.

Resources

Genetics Home Reference. (2010). Gaucher Disease. Retrieved on May 31, 2010 from Genetics Home Reference: https://ghr.nlm.nih.gov/condition=gaucher-disease

Mayo Clinic. (2009). Gaucher Disease. Retrieved on May 31, 2010 from the Mayo Clinic: https://www.mayoclinic.com/health/gauchers-disease/DS00972