What is MLD?

What is Metachromatic Leukodystrophy (MLD)?

Metachromatic leukodystrophy (MLD) is a rare genetically inherited disease that affecting 0.001% of the population. There are 3 forms to the disease, all of which result in life-long disability or death.

MLD, in plain speak, is a rare disease affecting about one in 100,000 people, where the lack of an important enzyme called arylsulfatase A causes your brain and nervous system to progressively lose function affecting: speech, memory, movement, sight, hearing, touch, eating and swallowing.

In scientific terms, MLD attacks the myelin sheath covering the nerve fibres of the brain. It is one of 36 known genetic demyelinating diseases or leukodystrophies.

It affects the body in ways not yet fully understood but we do know that there’s an accumulation of a fatty substance which affects the white matter of the brain and other areas of the body (liver, gall bladder, kidneys, and/or spleen), it gets worse over time, and there is currently no cure for MLD.

There are three types of MLD:

–        Late Infantile – between 1 and 2 years

–        Juvenile – 3 and 6 (early juvenile) or between ages 6 and 16 (late juvenile)

–        Adult – 17 or older / late teens

Life expectancy varies depending on what age the condition started, but the disease course usually runs 3 to 20 years or more. The earlier the age at diagnosis, the more quickly the disease progresses. Most children with the infantile form do not live past the age of five. Children with the juvenile form can live for up to 10 to 20 years after symptoms are first noticed. Adult cases have a greater life expectancy.

The disease is passed down through families. You must get a copy of the defective gene from both your parents to have the disease. Parents can each have the defective gene, but not have MLD.

Support groups like the Myelin Project, a US-based non-profit organisation with branches in Germany, the United Kingdom, and Italy, help raise awareness of such diseases and help prevent sufferers from feeling isolated.

Although there is currently no cure, research into MLD is being carried out in labs and hospitals throughout the world. Some progress has been made through gene therapy, and transplantation of the patient’s own bone marrow cells.

Frequently asked questions about MLD

MLD Frequently asked questions