Mucopolysaccharidosis: a rare disease?

summary

How mucopolysaccharide storage disease is inherited? Most of them are autosomal recessive diseases. Usually, both parents are carriers of disease-free genes. At this time, the children have a 25% probability of being sick individuals, a 50% probability of not being sick carriers, and a 25% probability of not being sick non carriers. The only exception is mucopolysaccharidosis type 2, which is an X-chromosome recessive genetic disease. The genetic situation is complex. Let me share my experience with you.

Mucopolysaccharidosis: a rare disease?

Enzyme replacement therapy, through artificial production of this enzyme and intravenous injection back to the patient. From type 1 to type 3 of mucopolysaccharidosis, related drugs have been put on the market. However, enzyme replacement therapy can not cure the symptoms, patients must receive intravenous injection every week for life, and the problems of intelligence and bone development can not be effectively solved. In addition, the price is expensive. Taking type I patients as an example, it costs 200000-300000 US dollars a year in the United States.

The principle of hematopoietic stem cell transplantation is that the transplanted stem cells produce normal enzymes. However, it is not easy to find a suitable match, and there are some risks and complications. At present, it is only effective for type 1, type 6 and type 7. In addition, there are certain restrictions on the age of patients, generally 3 years old is more appropriate.

The principle of gene therapy is to treat diseases by repairing gene mutation or introducing correct genes to express enzymes. In theory, this method can be used for one-time injection treatment, and it is hopeful to cure the root cause. The potential problem is safety and sustainability. There are many related studies in progress all over the world, and the clinical trials of gene therapy of type 3 are progressing the fastest. The type 1 and type 2 drugs developed by our laboratory in cooperation with Sangamo therapeutics have also entered the clinical trial stage.

matters needing attention

At present, enzyme replacement therapy has not entered the domestic market, while gene therapy is still in the state of research and development. The only choice for patients is bone marrow transplantation. Because of the difficulty of diagnosis, many patients have missed the best time of transplantation. Therefore, most patients have no medicine to treat.