trisomy 12p true ICD10:Q92.3 GARD:0005305 Trisomy 12p is an extremely rare chromosomal disorder (over 30 cases reported worldwide) characterized by craniofacial malformations (round face, prominent cheeks, high bulging forehead, broad and flat nasal bridge, short nose with anteverted nostrils, long philtrum, prominent and everted lower lip, low-set ears, abnormally folded helix, protuberant antihelix), postnatal growth retardation, mental and psychomotor retardation, generalized hypotonia, abnormally short wide hands and/or other abnormalities. UMLS:C0795845 MESH:C538299 chromosome 12p duplication Trisomy 12p is a chromosomal abnormality that results in developmental delay, intellectual impairment and a number of dysmorphic features including turricephaly, a flattened occiput, short neck, rounded facies with prominent cheeks, high prominent forehead, hypertelorism, epicanthic folds, broad nasal bridge and other facial dysmorphism. Cardiac and limb defects may occur. Structural brain abnormalities include polymicrogyria and focal cortical dysplasia. Seizures are often generalized, with myoclonic absences and myoclonic seizures reported, EEGs have shown 3Hz generalized spike-and-wave. Orphanet:1699 MONDO:0015723 12p duplication trisomy type 12p 12p trisomy Duplication 12p partial trisomy 12p chromosomal anomaly