Microcephalic osteodysplastic primordial dwarfism type II (MOPD II) is a form of primordial dwarfism associated with brain and skeletal abnormalities. It was characterized in 1982. MOPD II is listed as a rare disease by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This indicates that MOPD (or a subtype of MOPD) affects less than 200,000 people in the US population. It is associated with the protein pericentrin (PCNT). Intelligence is reported by usually within low-normal or mild intellectual disability range. Some have average levels of intelligence, but may masked by specific learning disability.

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Wiki: Microcephalic osteodysplastic primordial dwarfism