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.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, http://www.ncbi.nlm.nih.gov/Omim, MIM#100800, April 20, 2001)Osteochondrodysplasias: Abnormal development of cartilage and bone.Microcephaly: A congenital abnormality in which the CEREBRUM is underdeveloped, the fontanels close prematurely, and, as a result, the head is small. (Desk Reference for Neuroscience, 2nd ed.)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.Bone Diseases, DevelopmentalThanatophoric Dysplasia: A severe form of neonatal dwarfism with very short limbs. All cases have died at birth or later in the neonatal period.Growth Plate: The area between the EPIPHYSIS and the DIAPHYSIS within which bone growth occurs.Thyroid (USP): A dehydrated extract of thyroid glands from domesticated animals. After the removal of fat and connective tissue, the extract is dried or lyophilized to yield a yellowish to buff-colored amorphous powder containing 0.17-0.23% of iodine.Micrognathism: Abnormally small jaw.Bone Development: The growth and development of bones from fetus to adult. It includes two principal mechanisms of bone growth: growth in length of long bones at the epiphyseal cartilages and growth in thickness by depositing new bone (OSTEOGENESIS) with the actions of OSTEOBLASTS and OSTEOCLASTS.Growth Hormone: A polypeptide that is secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Growth hormone, also known as somatotropin, stimulates mitosis, cell differentiation and cell growth. Species-specific growth hormones have been synthesized.Cyclic GMP-Dependent Protein Kinase Type II: A cyclic GMP-dependent protein kinase subtype that is expressed predominantly in INTESTINES, BRAIN, and KIDNEY. The protein is myristoylated on its N-terminus which may play a role its membrane localization.Gigantism: The condition of accelerated and excessive GROWTH in children or adolescents who are exposed to excess HUMAN GROWTH HORMONE before the closure of EPIPHYSES. It is usually caused by somatotroph hyperplasia or a GROWTH HORMONE-SECRETING PITUITARY ADENOMA. These patients are of abnormally tall stature, more than 3 standard deviations above normal mean height for age.Brassinosteroids: Plant steroids ubiquitously distributed throughout the plant kingdom. They play essential roles in modulating growth and differentiation of cells at nanomolar to micromolar concentrations.Steroids, Heterocyclic: Steroidal compounds in which one or more carbon atoms in the steroid ring system have been substituted with non-carbon atoms.Chondrodysplasia Punctata: A heterogeneous group of bone dysplasias, the common character of which is stippling of the epiphyses in infancy. The group includes a severe autosomal recessive form (CHONDRODYSPLASIA PUNCTATA, RHIZOMELIC), an autosomal dominant form (Conradi-Hunermann syndrome), and a milder X-linked form. Metabolic defects associated with impaired peroxisomes are present only in the rhizomelic form.Chondrocytes: Polymorphic cells that form cartilage.Abnormalities, MultipleOsteopoikilosis: An asymptomatic, autosomal dominant trait in which pea-sized sclerotic spots, prominent in the metaphyseal area, are accompanied by unique cutaneous lesions. These are yellowish papules or plaques with increased elastin content. (From Cecil Textbook of Medicine, 19th ed, pp1434-35)Receptors, Somatotropin: Cell surface proteins that bind GROWTH HORMONE with high affinity and trigger intracellular changes influencing the behavior of cells. Activation of growth hormone receptors regulates amino acid transport through cell membranes, RNA translation to protein, DNA transcription, and protein and amino acid catabolism in many cell types. Many of these effects are mediated indirectly through stimulation of the release of somatomedins.Body Size: The physical measurements of a body.Cholestanols: Cholestanes substituted in any position with one or more hydroxy groups. They are found in feces and bile. In contrast to bile acids and salts, they are not reabsorbed.Gibberellins: A class of plant growth hormone isolated from cultures of Gibberella fujikuroi, a fungus causing Bakanae disease in rice. There are many different members of the family as well as mixtures of multiple members; all are diterpenoid acids based on the gibberellane skeleton.Limb Deformities, Congenital: Congenital structural deformities of the upper and lower extremities collectively or unspecified.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Cartilage: A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Metatarsal Bones: The five long bones of the METATARSUS, articulating with the TARSAL BONES proximally and the PHALANGES OF TOES distally.Pituitary Diseases: Disorders involving either the ADENOHYPOPHYSIS or the NEUROHYPOPHYSIS. These diseases usually manifest as hypersecretion or hyposecretion of PITUITARY HORMONES. Neoplastic pituitary masses can also cause compression of the OPTIC CHIASM and other adjacent structures.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Bone and Bones: A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.