Tetrasomy 9p is a rare autosomal anomaly characterized by pre- and postnatal growth retardation, psychomotor delay, mild to moderate intellectual disability, hypotonia, microcephaly, dysmorphic features (ocular hypertelorism, low-set, malformed ears, bulbous/beaked nose, microretrognathia, enophthalmos/micropthalmia, epicanthus, strabismus), cleft lip/palate, skeletal abnormalities (hypoplastic nails/distal phalanges, short stature, short neck, contractures), congenital heart defects, renal and urogenital malformations (renal hypoplasia, genital hypoplasia, cryptorchidism). The disease is MONDO_0018030 (tetrasomy 9p). Also known as: Chromosome 9, Tetrasomy 9p, Isochromosome 9p, tetrasomy type 9p.