The range and severity of symptoms varies among individuals with trichorhinophalangeal syndrome type II. Affected individuals will not have all of the symptoms listed below. The most common symptoms include fine, thin hair; unusual facial features; short stature; abnormalities of the hands and feet; and/or development of multiple bony growths (exostoses) projecting outward from the surfaces of various bones of the body. Additional characteristic abnormalities may include mental retardation, Diminished muscle tone (hypotonia), and/or skin abnormalities.
Affected infants may exhibit markedly thin, Sparse hair at birth (congenital); the hair may also be abnormally brittle and/or may grow slowly. Affected individuals may lose most or all of their scalp hair (alopecia) at a young age, in some cases, by the second decade of life.
Infants with TRPS2 may also have abnormalities of the head and facial (craniofacial) area including a condition known as microcephaly, which indicates that the head circumference is smaller than would be expected for age and sex. Additional features may include an abnormally large, rounded (bulbous) nose with a broad nasal bridge and thick wide nostrils (tented alae); large, protruding ears; and/or an abnormally small jaw (micrognathia) that may be displaced father back than normal (retrognathia). Affected infants may also exhibit a prominent, elongated groove in the upper lip (philtrum); a thin upper lip that may droop; deep-set eyes; widely spaced eyes (ocular hyperterlorism); and/or deviation of one eye away from the other (exotropia). In some cases, children with TRPS2 may also have dental abnormalities such as extra teeth (supernumerary central incisors) and/or absence of certain teeth.
During infancy, Growth delays (retardation) may also be present. Growth retardation is typically progressive, resulting in Short stature (dwarfism). In most cases, individuals with TRPS2 may also have abnormally short fingers and toes (brachydactyly), resulting, in part, from “cone-shaped” development of the “growing ends” of certain bones in the hands and feet (epiphyseal coning). In addition, the nails may be thin and brittle and, in some cases, the fifth fingers may be abnormally bent (clinodactyly). As affected individuals age, they may develop numerous bony growths (exostoses) that may project outward from the surface of various bones (e.g., pelvis, long bones, shoulder blade) in the body. In some cases, the development of multiple exostoses may result in compression of the spinal cord, certain nerves, and/or blood vessels; unequal (asymmetric) growth of the limbs; and/or limitations in movements. In addition, some affected individuals may be abnormally prone to bone fractures. Additional Skeletal abnormalities may also be present including thin, narrow ribs; unusual “wing-like” shoulder blades (winged scapula); webbing (syndactyly) of certain fingers and toes; and/or abnormalities of the spinal column including sideways curvature of the spine (scoliosis).
Some individuals with TRPS2 may develop hip problems similar to those experienced by people with Legg-Calve-Perthes disease including progressive degeneration of the end portion (head) of the thighbone (capital femoral epiphyseal osteonecrosis).
In many affected infants, mild to severe Mental retardation is present at birth. In other cases, Mental retardation may not become obvious until late infancy or childhood. However, in approximately 25 percent of affected individuals, intelligence may be normal.
Affected newborns may also exhibit additional physical abnormalities including excess (redundant) skin, numerous discolored elevated spots on the skin (maculopapular nevi), Diminished muscle tone (hypotonia), and/or abnormally flexible (hyperextensible) joints. As affected children age, excess skin may appear tighter and muscle tone may improve; however, skin Lesions may become more numerous. Affected infants may also exhibit Hearing loss (sensorineural deafness) and delays in the development of speech. In some cases, individuals affected with TRPS2 may be susceptible to frequent respiratory infections. In some cases, affected individuals may have additional abnormalities affecting the genito-urinary tract (e.g., accumulation of fluid in the uterus (hydrometrocolpos) and blood in the uterus (hematometra) in females, ureteral reflux, etc.).