Families

What is PLAA-related disorder?
PLAA-related disorder is an extremely rare genetic condition that affects the brain and nervous system. Its full medical name is "Neurodevelopmental Disorder with Progressive Microcephaly, Spasticity, and Brain Anomalies," sometimes shortened to NDMSBA. It is caused by changes (mutations) in a gene called PLAA, which plays an important role in how brain cells communicate and recycle their building blocks.

How rare is it?
This condition is ultra-rare. As of the most recent medical reports, only about 6 to 10 families worldwide have been identified with this disorder. Cases have been found in families from the Middle East, the United Kingdom, China, and other regions, meaning it can affect people of any ethnic background.

How is it inherited?
In most cases, PLAA-related disorder follows an autosomal recessive pattern of inheritance. This means:
•    A child must inherit two faulty copies of the PLAAgene — one from each parent — to develop the condition.
•    Parents who each carry one faulty copy are called "carriers." Carriers are healthy and do not show symptoms.
•    When both parents are carriers, there is a 1 in 4 (25%) chance with each pregnancy that the child will be affected.
•    The condition is more common in families where the parents are related (consanguineous), because related parents are more likely to carry the same gene change.

More recently, a milder form has been described in children who have only one new (not inherited from a carrier parent) faulty copy of the gene. These children may have milder learning difficulties or autism-like features.