What is Gaucher Disease? Gaucher (pronounced go-SHAY) disease is a rare, genetic condition in which people do not have, or have a faulty version of, an enzyme called glucocerebrosidase that recycles materials used by cells in normal daily life. The absence of this enzyme causes a fatty substance (glucocerebroside) to build up in certain types of cells, enlarging them. These enlarged cells, called Gaucher cells, collect in certain organs and tissues (e.g. the spleen, liver and bones). This prevents them from functioning normally and causes the signs and symptoms of Gaucher disease. The main signs and symptoms of Gaucher disease are an enlarged liver and spleen (hepatosplenomegaly), problems with bones and joints, low blood platelet count (thrombocytopenia), and low haemoglobin count (anaemia). Gaucher disease symptoms vary widely between people and some people may suffer very few symptoms.