The mucopolysaccharide diseases are caused by such recessive genes. In all MPS and related disorders except Hunter Disease, both men and women can be carriers. The effects vary from one disease to another. Some sufferers may be mildly affected, but for many the diseases cause severe disabilities. In most cases growth is restricted.
Some diseases cause progressive mental as well as physical handicap.
Those diseases causing severe mental handicap may also lead to death in childhood. At present there is no cure. Research funded by the MPS Society on Gene Therapy for Hurler Disease was carried out on three patients in 1998. This is being developed jointly by Biomarin and Genzyme pharmaceutical companies. Early indications from the clinical trials are promising, but there are still serious obstacles to overcome if there is to be enzyme replacement therapy for all types of Mucopolysaccharide and related diseases.