Achondroplasia: An autosomal dominant disorder that is the most frequent form of short-limb dwarfism. Affected individuals exhibit short stature caused by rhizomelic shortening of the limbs, characteristic facies with frontal bossing and mid-face hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, GENU VARUM, and trident hand. (Online Mendelian Inheritance in Man,, MIM#100800, April 20, 2001)Receptor, Fibroblast Growth Factor, Type 3: A fibroblast growth factor receptor that regulates CHONDROCYTE growth and CELL DIFFERENTIATION. Mutations in the gene for fibroblast growth factor receptor 3 have been associated with ACHONDROPLASIA; THANATOPHORIC DYSPLASIA and NEOPLASTIC CELL TRANSFORMATION.Thanatophoric Dysplasia: A severe form of neonatal dwarfism with very short limbs. All cases have died at birth or later in the neonatal period.Bone Diseases, DevelopmentalReceptors, Fibroblast Growth Factor: Specific molecular sites or structures on cell membranes that react with FIBROBLAST GROWTH FACTORS (both the basic and acidic forms), their analogs, or their antagonists to elicit or to inhibit the specific response of the cell to these factors. These receptors frequently possess tyrosine kinase activity.Paternal Age: Age of the biological father.Dwarfism: A genetic or pathological condition that is characterized by short stature and undersize. Abnormal skeletal growth usually results in an adult who is significantly below the average height.Judaism: The religion of the Jews characterized by belief in one God and in the mission of the Jews to teach the Fatherhood of God as revealed in the Hebrew Scriptures. (Webster, 3d ed)Tomography, X-Ray: Tomography using x-ray transmission.Spinal Canal: The cavity within the SPINAL COLUMN through which the SPINAL CORD passes.Growth Plate: The area between the EPIPHYSIS and the DIAPHYSIS within which bone growth occurs.Osteochondrodysplasias: Abnormal development of cartilage and bone.Ophthalmoscopes: Devices for examining the interior of the eye, permitting the clear visualization of the structures of the eye at any depth. (UMDNS, 1999)Musculoskeletal Abnormalities: Congenital structural abnormalities and deformities of the musculoskeletal system.