Petra Oliva, PhD, Archimed Life Science, discusses newborn screening for metachromatic leukodystrophy (MLD).
MLD is a genetic disorder caused by mutations in the ARSA or PSAP genes, which result in a deficiency of the enzyme arylsulfatase A and a decreased ability to break down sulfatides. The disease is characterized by the toxic buildup of lipids and other storage materials in cells that impairs the myelin sheath surrounding neurons.
There is no cure for MLD. Bone marrow transplantation may delay progression of the disease in some infantile-onset cases. Other treatments are based on symptom management. A gene replacement therapy has recently been approved in Europe, with plans to expand to the United States.
Newborn screening plays a pivotal role in the diagnosis of MLD due to very few clinical manifestations presenting at birth. Because of delayed diagnosis, once clinical manifestations do present later on, decline is rapid due to the progressive nature of the disease. When MLD is detected in newborn screening, treatments can start sooner and have better outcomes for the patient.
A study conducted in Germany observed the effects of adding MLD to the newborn screening panel. Over 140,000 babies have been screened in this pilot study, with four identified MLD cases. These patients were then referred to treatment centers. Currently, there is preparation for GBA submission to make MLD mandatory in newborn screening. The study is also expanding to other countries, including over 18,000 participants in Austria.
For more information on MLD and other rare lysosomal storage disorders, visit https://checkrare.com/diseases/lysosomal-storage-disorders/
