Children's Hospital Colorado

MECP2 Duplication Syndrome

What is MECP2 duplication syndrome?

MECP2 duplication syndrome (MDS) is a neurological and developmental disorder. This is a MECP2-related disorder, which means the disorder is caused by a change in the MECP2 gene. This condition affects boys and girls.

Children with MDS have delayed language development and problems with hand use and walking. These symptoms can be seen with many different neurological and developmental disorders. Having a specific diagnosis of MDS (or other genetic disorder) may help you understand what to expect.

What causes MECP2 duplication syndrome?

MDS involves a change in a child's DNA, which results in an extra copy of a gene called the MECP2 gene. This gene occurs on the X chromosome. Even though this is a genetic disorder, it may be new to the patient and not inherited from parents. In other words, a new spelling mistake happened around the time the egg and sperm came together. This is not caused by something the parents did or didn't do. Sometimes the mother may carry the extra copy of the MECP2 gene but does not have symptoms of MDS.

Who gets MECP2 duplication syndrome?

MDS is so rare that we do not know yet how often it happens. MDS is often, but not always, seen in males.