- Aortic valve stenosis (HP:0001650): The presence of a stenosis (narrowing) of the aortic valve. Evidence: IEA. (OMIM:253010)
- Opacification of the corneal stroma (HP:0007759): Reduced transparency of the stroma of cornea. Evidence: IEA. (OMIM:253010)
- Corneal opacity (HP:0007957): A reduction of corneal clarity. Evidence: PCS. Frequency: 3/9. (PMID:33558080)
- Constricted iliac wing (HP:0003277). Evidence: IEA. (OMIM:253010)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: IEA. (OMIM:253010)
- Grayish enamel (HP:0000683): A gray discoloration of the dental enamel. Evidence: IEA. (OMIM:253010)
- Hypoplasia of the odontoid process (HP:0003311): Developmental hypoplasia of the dens of the axis. Evidence: PCS. Frequency: 14/19. (OMIM:253010;PMID:33558080)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Coarse facial features (HP:0000280): Absence of fine and sharp appearance of brows, nose, lips, mouth, and chin, usually because of rounded and heavy features or thickened skin with or without thickening of subcutaneous and bony tissues. Evidence: PCS. Frequency: 6/9. (PMID:33558080)
- Intimal thickening in the coronary arteries (HP:0005292). Evidence: IEA. (OMIM:253010)
- Thin corpus callosum (HP:0033725): An abnormally thin corpus callous, due to atrophy, hypoplasia or agenesis. This term is intended to be used in situations where it is not known if thinning of the corpus callosum (for instance, as visualized by magnetic resonance tomography) is due to abnormal development (e.g. a leukodystrophy) or atrophy following normal development (e.g. neurodegeneration). Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Chondroitin sulfate excretion in urine (HP:0012070): An increased concentration of chondroitin sulfate (CHEBI:37397) in the urine. Evidence: PCS. Frequency: 4/9. (PMID:33558080)
- Hyperlordosis (HP:0003307): Abnormally increased curvature (anterior concavity) of the lumbar or cervical spine. Evidence: IEA. (OMIM:253010)
- Cervical subluxation (HP:0003308): A partial dislocation of one or more intervertebral joints in the cervical vertebral column. Evidence: IEA. (OMIM:253010)
- Genu valgum (HP:0002857): The legs angle inward, such that the knees are close together and the ankles far apart. Evidence: IEA. Frequency: 4/9. (OMIM:253010)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: PCS. Frequency: 0/9. (PMID:33558080)
- Disproportionate short-trunk short stature (HP:0003521): A type of disproportionate short stature characterized by a short trunk but a average-sized limbs. Evidence: IEA. (OMIM:253010)
- Ulnar deviation of the wrist (HP:0003049). Evidence: IEA. (OMIM:253010)
- Hip dysplasia (HP:0001385): The presence of developmental dysplasia of the hip. Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Pointed proximal second through fifth metacarpals (HP:0001223): All of the metacarpal bones of the hand have a pointed proximal appearance. Evidence: IEA. (OMIM:253010)
- Coxa valga (HP:0002673): Coxa valga is a deformity of the hip in which the angle between the femoral shaft and the femoral neck is increased compared to age-adjusted values (about 150 degrees in newborns gradually reducing to 120-130 degrees in adults). Evidence: IEA. (OMIM:253010)
- Joint stiffness (HP:0001387): Joint stiffness is a perceived sensation of tightness in a joint or joints when attempting to move them after a period of inactivity. Joint stiffness typically subsides over time. Evidence: PCS. Frequency: 1/9. (PMID:33558080)
- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: IEA. (OMIM:253010)
- Keratan sulfate excretion in urine (HP:0012069): An increased concentration of keratan sulfate in the urine. Evidence: TAS. (OMIM:253010)
- Decreased beta-galactosidase activity (HP:0008166): Abnormally decreased rate of beta-galactosidase activity. Beta-galactosidase activity can be measured in leukocyte, fibroblast, or plasma. Evidence: PCS. (PMID:33558080)
- Platyspondyly (HP:0000926): A flattened vertebral body shape with reduced distance between the vertebral endplates. Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:33558080)
- Prominent sternum (HP:0000884). Evidence: IEA. (OMIM:253010)
- Recurrent upper respiratory tract infections (HP:0002788): An increased susceptibility to upper respiratory tract infections as manifested by a history of recurrent upper respiratory tract infections (running ears - otitis, sinusitis, pharyngitis, tonsillitis). Evidence: IEA. (OMIM:253010)
- Mitral regurgitation (HP:0001653): An abnormality of the mitral valve characterized by insufficiency or incompetence of the mitral valve resulting in retrograde leaking of blood through the mitral valve upon ventricular contraction. Evidence: PCS. Frequency: 5/9. (PMID:33558080)
- Widely spaced teeth (HP:0000687): Increased spaces (diastemata) between most of the teeth in the same dental arch. Evidence: IEA. (OMIM:253010)
- Bilateral talipes equinovarus (HP:0001776): Bilateral clubfoot deformity. Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Metaphyseal widening (HP:0003016): Abnormal widening of the metaphyseal regions of long bones. Evidence: IEA. (OMIM:253010)
- Inguinal hernia (HP:0000023): Protrusion of the contents of the abdominal cavity through the inguinal canal. Evidence: IEA. (OMIM:253010)
- Epiphyseal deformities of tubular bones (HP:0003053). Evidence: IEA. (OMIM:253010)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: PCS. Frequency: 2/9. (PMID:33558080)
- Hypoplasia of the capital femoral epiphysis (HP:0003090): Underdevelopment of the proximal epiphysis of the femur. Evidence: PCS. Frequency: 4/9. (PMID:33558080)
- Osteoporosis (HP:0000939): Osteoporosis is a systemic skeletal disease characterized by low bone density and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility. According to the WHO criteria, osteoporosis is defined as a BMD that lies 2.5 standard deviations or more below the average value for young healthy adults (a T-score below -2.5 SD). Evidence: IEA. (OMIM:253010)
- Cervical myelopathy (HP:0002318): A collection of pathologic conditions that result from progressive spinal cord dysfunction secondary to cord compression in the cervical spine. Evidence: IEA. (OMIM:253010)
- Wide mouth (HP:0000154): Distance between the oral commissures more than 2 SD above the mean. Alternatively, an apparently increased width of the oral aperture (subjective). Evidence: IEA. (OMIM:253010)
- Carious teeth (HP:0000670): Caries is a multifactorial bacterial infection affecting the structure of the tooth. This term has been used to describe the presence of more than expected dental caries. Evidence: IEA. (OMIM:253010)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: IEA. (OMIM:253010)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: PCS. Frequency: 1/9. (PMID:33558080)
- Ovoid vertebral bodies (HP:0003300): When viewed in lateral radiographs, vertebral bodies have a roughly rectangular configuration. This term applies if the vertebral body appears rounded or oval. Evidence: IEA. (OMIM:253010)
- Restrictive ventilatory defect (HP:0002091): A functional defect characterized by reduced total lung capacity (TLC) not associated with abnormalities of expiratory airflow or airway resistance. Spirometrically, a restrictive defect is defined as FEV1 (forced expiratory volume in 1 second) and FVC (forced vital capacity) less than 80 per cent. Restrictive lung disease may be caused by alterations in lung parenchyma or because of a disease of the pleura, chest wall, or neuromuscular apparatus. Evidence: IEA. (OMIM:253010)
- Kyphosis (HP:0002808): Exaggerated anterior convexity of the thoracic vertebral column. Evidence: PCS. Frequency: 3/9. (PMID:33558080)
- Flaring of rib cage (HP:0000904): The presence of wide, concave anterior rib ends. Evidence: IEA. (OMIM:253010)
- Dysostosis multiplex (HP:0000943). Evidence: PCS. Frequency: 6/9. (PMID:33558080)
- Mandibular prognathia (HP:0000303): Abnormal prominence of the chin related to increased length of the mandible. Evidence: IEA. (OMIM:253010)
These phenotypes are associated with the disease mucopolysaccharidosis type 4B (OMIM:253010).