Question: What are the symptoms of Thanatophoric dysplasia ?
Answer: What are the signs and symptoms of Thanatophoric dysplasia? The Human Phenotype Ontology provides the following list of signs and symptoms for Thanatophoric dysplasia. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of the femur 90% Abnormality of the metaphyses 90% Abnormality of the sacroiliac joint 90% Aplasia/Hypoplasia of the lungs 90% Bowing of the long bones 90% Brachydactyly syndrome 90% Cognitive impairment 90% Cutis laxa 90% Depressed nasal bridge 90% Increased nuchal translucency 90% Macrocephaly 90% Malar flattening 90% Micromelia 90% Muscular hypotonia 90% Narrow chest 90% Platyspondyly 90% Respiratory insufficiency 90% Short stature 90% Short thorax 90% Skeletal dysplasia 90% Small face 90% Split hand 90% Abnormality of neuronal migration 50% Frontal bossing 50% Hearing impairment 50% Intrauterine growth retardation 50% Kyphosis 50% Polyhydramnios 50% Proptosis 50% Ventriculomegaly 50% Abnormality of the kidney 7.5% Acanthosis nigricans 7.5% Atria septal defect 7.5% Cloverleaf skull 7.5% Hydrocephalus 7.5% Joint hypermobility 7.5% Limitation of joint mobility 7.5% Low-set, posteriorly rotated ears 7.5% Patent ductus arteriosus 7.5% Seizures 7.5% Autosomal dominant inheritance - Decreased fetal movement - Flared metaphysis - Heterotopia - Hypoplastic ilia - Intellectual disability, profound - Lethal short-limbed short stature - Metaphyseal irregularity - Neonatal death - Severe platyspondyly - Severe short stature - Short long bone - Short ribs - Short sacroiliac notch - Small abnormally formed scapulae - Small foramen magnum - Wide-cupped costochondral junctions - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Thanatophoric dysplasia ?
Answer: What causes thanatophoric dysplasia? Thanatophoric dysplasia is caused by mutations in the FGFR3 gene. This gene provides instructions for making a protein that is involved in the development and maintenance of bone and brain tissue. Mutations in this gene cause the FGFR3 protein to be overly active, which leads to the severe problems with bone growth that are seen in thanatophoric dysplasia. It is not known how FGFR3 mutations cause the brain and skin abnormalities associated with this disorder.
Source: GARD