Qazi-Markouizos syndrome is a rare condition that affects muscle tone, skeletal development, and neurological function. It is characterized by non-progressive central hypotonia (low muscle tone), chronic constipation, severe psychomotor retardation, abnormal dermatoglyphics (unusual skin ridge patterns), dysharmonic skeletal maturation (uneven bone development), and disproportionate muscle fibers. Seizures or abnormal findings on an electroencephalograph have also been reported in some cases. This syndrome has been identified in three unrelated Puerto Rican boys. It is known by several names that emphasize its features, such as dysharmonic skeletal maturation with muscular fiber disproportion and congenital fiber type disproportion. The information provided here is based on established definitions and curated rare disease entries.

People with this condition commonly have low central muscle tone, severe delays in motor development (psychomotor retardation), chronic constipation, and unusual skin ridge patterns (abnormal dermatoglyphics). In addition, the syndrome includes uneven bone development and disproportionate muscle fibers. Some individuals may also experience seizures or show abnormal results on brain wave tests (EEG).

Information about causes is currently limited for this condition.