Soto's syndrome. X-ray of scoliosis (curved spine) in a 10-year-old boy with Soto's syndrome. The top of the spine is at top in this posterior view of the spinal vertebrae. Soto's syndrome is a rare genetic disorder where excessive growth is seen in the first 2-3 years of life. This can lead to the deformation of the spine seen here. Other symptoms may include hypotonia (low muscle tone), mild mental retardation, clumsiness and speech impairments. It is not life-threatening and the abnormalities usually resolve with time.