People with dwarfism have short stature. This means that their height is under 4' 10" as an adult. They are usually of normal intelligence. Dwarfism most often does happen in families where both parents are of average height.

More than 300 different conditions can cause dwarfism. Achondroplasia is the most common type of dwarfism. Achondroplasia is a genetic condition that affects about 1 in 15,000 to 1 in 40,000 people. It makes your arms and legs short in comparison to your head and trunk. You may also have a larger head and weak muscle tone. Other genetic conditions, kidney disease, and problems with metabolism or hormones can also cause dwarfism.

The conditions that cause dwarfism can also cause other health problems. Most of them are treatable. It is important to have regular checkups throughout your life. With proper medical care, most people with dwarfism have active lives and live as long as other people.

Some types of dwarfism can be identified through prenatal testing if a doctor suspects a particular condition and tests for it. However, most cases are not identified until after the child is born. In those instances, the doctor makes a diagnosis based on the child's appearance, failure to grow, and X-rays of the bones. Depending on the type of dwarfism the child has, diagnosis often can be made almost immediately after birth. Once a diagnosis is made, there is no "treatment" for most of the conditions that lead to short stature. Hormonal or metabolic problems may be treated with hormone injections or special diets to spark a child's growth, but skeletal dysplasias cannot be "cured." Individuals who are interested in learning whether they or family members have, or are at risk for, dwarfism should speak with their health care provider or a genetics professional.

Achondroplasia is a disorder of bone growth that prevents the changing of cartilage (particularly in the long bones of the arms and legs) to bone. It is characterized by dwarfism, limited range of motion at the elbows, large head size (macrocephaly), small fingers, and normal intelligence. Achondroplasia can cause health complications such as interruption of breathing (apnea), obesity, recurrent ear infections, an exaggerated inward curve of the lumbar spine (lordosis). More serious problems include a narrowing of the spinal canal that can pinch (compress) the upper part of the spinal cord (spinal stenosis) and a buildup of fluid in the brain (hydrocephalus). Some people with achondroplasia may have delayed motor development early on, but cognition is normal.

Achondroplasia is caused by mutations in the FGFR3 gene. Inheritance is autosomal dominant. Treatment may include medication with growth hormone, and surgery aimed to correct the spine, or bone problems, as well, as to reduce the pressure inside the brain in cases of hydrocephaly. Prognosis with achondroplasia is good except in cases of y spinal compression at the neck.

Cockayne syndrome is a rare disease which causes short stature, premature aging (progeria), severe photosensitivity, and moderate to severe learning delay. This syndrome also includes failure to thrive in the newborn, very small head (microcephaly), and impaired nervous system development. Other symptoms may include hearing loss, tooth decay, vision problems, and bone abnormalities. There are three subtypes according to the severity of the disease and the onset of the symptoms:

• Cockayne syndrome type 1 (type A), sometimes called “classic” or "moderate" Cockayne syndrome, diagnosed during early childhood
• Cockayne syndrome type 2 (type B), sometimes referred to as the “severe” or "early-onset" type, presenting with growth and developmental abnormalities at birth
• Cockayne syndrome type 3 (type C), a milder form of the disorder

Cockayne syndrome is caused by mutations in either the ERCC8 (CSA) or ERCC6 (CSB) genes. Inheritance is autosomal recessive. Type 2 is the most severe and affected people usually do not survive past childhood. Those with type 3 live into middle adulthood. There is no cure yet. Treatment is supportive and may include educational programs for developmental delay, physical therapy, gastrostomy tube placement as needed; medications for spasticity and tremor as needed; use of sunscreens and sunglasses; treatment of hearing loss and cataracts; and other forms of treatment, as needed.

Congenital hypothyroidism is a condition that affects infants from birth and results from a partial or complete loss of thyroid function (hypothyroidism). The thyroid gland makes hormones that play an important role in regulating growth, brain development, and metabolism in the body. Congenital hypothyroidism occurs when the thyroid gland fails to develop or function properly. In the United States and many other countries, all newborns are tested for congenital hypothyroidism as part of newborn screening. If untreated, congenital hypothyroidism can lead to intellectual disability and abnormal growth. If treatment begins in the first month after birth, infants usually develop normally. Treatment involves medication to replace the missing thyroid hormones, such as levothyroxine. Most cases of congenital hypothyroidism occur in people with no history of the disorder in their family. About 15-20% of cases are due to an underlying gene mutation. Rarely, congenital hypothyroidism can be a symptom included in a larger genetic disorder called a syndrome.

Pituitary dwarfism is a form of dwarfism caused by complete or partial growth hormone deficiency, resulting from either the lack of growth hormone-releasing factor from the hypothalamus or from the mutations in the growth hormone gene (GH1) in the pituitary gland. it is also known as Type I pituitary dwarfism. Human hypophysial dwarf is caused by a deficiency of human growth hormone during development.