MedGen

While the majority of individuals with Costello syndrome share characteristic findings affecting multiple organ systems, the phenotypic spectrum is wide, ranging from a milder or attenuated phenotype to a severe phenotype with early lethal complications. Costello syndrome is typically characterized by failure to thrive in infancy as a result of severe postnatal feeding difficulties; short stature; developmental delay or intellectual disability; coarse facial features (full lips, large mouth, full nasal tip); curly or sparse, fine hair; loose, soft skin with deep palmar and plantar creases; papillomata of the face and perianal region; diffuse hypotonia and joint laxity with ulnar deviation of the wrists and fingers; tight Achilles tendons; and cardiac involvement including: cardiac hypertrophy (usually typical hypertrophic cardiomyopathy), congenital heart defect (usually valvar pulmonic stenosis), and arrhythmia (usually supraventricular tachycardia, especially chaotic atrial rhythm/multifocal atrial tachycardia or ectopic atrial tachycardia). Relative or absolute macrocephaly is typical, and postnatal cerebellar overgrowth can result in the development of a Chiari I malformation with associated anomalies including hydrocephalus or syringomyelia. Individuals with Costello syndrome have an approximately 15% lifetime risk for malignant tumors including rhabdomyosarcoma and neuroblastoma in young children and transitional cell carcinoma of the bladder in adolescents and young adults. [from GeneReviews]

Abnormally increased body weight. [from HPO]

Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. [from HPO]

Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium. [from HPO]

Nonsyndromic cleft lip with or without cleft palate is a complex disease with a wide phenotypic spectrum ranging from notches of the vermilion and/or grooves in the philtrum to complete unilateral and bilateral clefts of the lip and palate (summary by Neiswanger et al., 2007). Genetic Heterogeneity of Orofacial Cleft Isolated cleft lip with or without cleft palate (CL/P) is genetically heterogeneous. The OFC1 locus has been mapped to chromosome 6p24. Other CL/P loci have been mapped to 2p13 (OFC2; 602966), 19q13 (OFC3; 600757), 4q (OFC4; 608371), 13q33.1-q34 (OFC9; 610361), 8q24.3 (OFC12; 612858), and 1p33 (OFC13; 613857). OFC5 (608874) is caused by mutation in the MSX1 gene (142983) on 4p16; OFC6 (608864) is associated with variation in an enhancer of the IRF6 gene (607199) on 1q; OFC7 (see 225060) is associated with mutation in the NECTIN1 gene (600644) on 11q23; OFC8 (618149) is caused by mutation in the TP63 gene (603273) on 3q28; OFC10 (613705) is associated with haploinsufficiency of the SUMO1 gene (601912) on 2q33; OFC11 (600625) is caused by mutation in the BMP4 gene (112262) on 14q22; OFC14 (615892) is associated with a 273-kb deleted region on 1p31; and OFC15 (616788) is caused by mutation in the DLX4 gene (601911) on 17q21. A common polymorphism in the MTR gene (156570.0008) has been associated with susceptibility to orofacial clefting. Cleft lip with or without cleft palate has been found in association with gastric cancer (see 137215) in individuals with mutation in the CDH1 gene (192090). [from OMIM]

A relatively mild degree of macrocephaly in which the head circumference is not above two standard deviations from the mean, but appears dysproportionately large when other factors such as body stature are taken into account. [from HPO]

A sudden movement downward, usually resulting in injury. [from NCI]

Deviation from the norm of height with respect to that which is expected according to age and gender norms. [from HPO]

A rare genetic developmental defect during embryogenesis with characteristics of distinct facial features (long triangular face, broad forehead, narrow nose and mandible, high arched palate), prominent, dysmorphic ears (low-set and cup-shaped with large conchae and hypoplastic tragus, antitragus and lobe), long neck, preauricular and/or branchial fistulas and/or cysts, hypoplastic cervical muscles with sloping shoulders and clavicles, winged, low, and laterally-set scapulae, hearing impairment and mild intellectual deficit. Vertebral defects and short stature may also be associated. [from SNOMEDCT_US]