Anna Haining Bates with her parents

Greek gigas, gigantus ("giant") is a condition characterized by excessive height growth and bigness. As a menstrual term, gigantism is rarely used except to refer to the rare condition of pituitary gigantism due to prepubertal growth hormone excess. There is no precise definition of the degree of height that qualifies a person to be termed a "giant." The term has been typically applied to those whose height is not just in the upper 1% of the population but several standard deviations above mean for persons of the same sex, age, and ethnic ancestry. Typical adult heights of Americans and Europeans to whom the term might be applied are 225 - 240 cm (7'6" - 8 feet). The term is not applied to those whose heights appear to be the healthy result of normal genetics and nutrition. Image File history File links Anna_Swan_with_her_parents. ... Image File history File links Anna_Swan_with_her_parents. ... This article or section does not cite any references or sources. ... Growth hormone (GH or somatotropin) is a 191-amino acid, single chain polypeptide hormone which is synthesised, stored and secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland, which stimulates growth and cell reproduction in humans and other animals. ... In probability and statistics, the standard deviation of a probability distribution, random variable, or population or multiset of values is a measure of the spread of its values. ... A foot (plural: feet or foot;[1] symbol or abbreviation: ft or, sometimes, ′ – a prime) is a unit of length, in a number of different systems, including English units, Imperial units, and United States customary units. ... DNA, the molecular basis for inheritance. ...

Pituitary gigantism

Pituitary growth hormone excess is the single condition that accounts for nearly all cases of pathologic extreme height. The excess growth hormone usually results from oversecretion by a group of somatotrope cells of the anterior pituitary gland (termed a "somatotrope adenoma"). These cells do not respond to normal controls of growth or function. They grow very slowly, so that for many years the only effects of such an adenoma are the secretion of excessive growth hormone. Over decades, such an adenoma may reach a large enough size (2 cm or more in diameter) to cause headaches, impair vision, or damage other pituitary functions. Many years of growth hormone excess can cause other problems as well. Located at the base of the skull, the pituitary gland is protected by a bony structure called the sella turcica. ... Growth hormone (GH or somatotropin) is a 191-amino acid, single chain polypeptide hormone which is synthesised, stored and secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland, which stimulates growth and cell reproduction in humans and other animals. ... Somatotropes are cells in the anterior pituitary which produce growth hormone. ... The anterior pituitary (also called the adenohypophysis) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. ... An adenoma is a collection of growths (-oma) of glandular origin. ...

The primary effect of growth hormone excess in childhood is excessive growth, but the extreme height is accompanied by a characteristic physique recognizable to an endocrinologist. The typical physique involves heavy, thick bones, with large hands and feet and a heavy jaw. Once puberty is complete and adult height is achieved, continued thickening of the skin and growth of the jaw results in a combination of features referred to as acromegaly. Endocrinology is a branch of medicine dealing with disorders of the endocrine system and its specific secretions called hormones. ... Grays Anatomy illustration of a human femur. ... Puberty refers to the process of physical changes by which a childs body becomes an adult body capable of reproduction. ... Acromegaly (from Greek akros high and megas large - extremities enlargement) is a hormonal disorder that results when the pituitary gland produces excess growth hormone (hGH). ...

If a physician suspects pituitary gigantism or acromegaly, the simplest diagnostic screening test is measurement of insulin-like growth factor 1 in the blood. This is usually quite elevated but levels must be interpreted in relation to age and pubertal status. Additional confirmatory testing may include magnetic resonance imaging (MRI) of the pituitary to look for a visible adenoma, and suppressibility of growth hormone levels by glucose. Treatment depends on the size of the adenoma and may involve removal by a neurosurgeon, drugs such as octreotide or bromocriptine, or radiation. Treatment is discussed in more detail in the acromegaly article. Insulin-like growth factor 1 (IGF-1) is a polypeptide protein hormone similar in molecular structure to insulin. ... Magnetic Resonance Image showing a median sagittal cross section through a human head. ... Glucose (Glc), a monosaccharide (or simple sugar), is the most important carbohydrate in biology. ... Somatostatin is a hormone. ... Bromocriptine is an ergoline derivative dopamine agonist that is used in the treatment of pituitary tumors and Parkinsons disease. ... Acromegaly (from Greek akros high and megas large - extremities enlargement) is a hormonal disorder that results when the pituitary gland produces excess growth hormone (hGH). ...

Childhood pituitary gigantism is a rare condition, and those affected are often unusual enough to attain a degree of celebrity status (for example, André the Giant and The Great Khali). Acromegaly is the term used for the condition of growth hormone excess when it occurs in adults. Acromegaly is a far more common disease in adults than pituitary gigantism is in children. André the Giant was the stage name of André René Roussimoff, (May 19, 1946 – January 27, 1993) a French professional wrestler and actor. ... Dalip Singh Rana[2] (born August 27, 1972) is an Indian professional wrestler and actor, better known by his ring name The Great Khali. ... Acromegaly (from Greek akros high and megas large - extremities enlargement) is a hormonal disorder that results when the pituitary gland produces excess growth hormone (hGH). ...

Other conditions of overgrowth or excessive tallness in childhood

Children who are excessively tall are often referred to as Giantigionists. The majority of children who seem excessively tall or large to their parents usually have a combination of simple familial tallness and childhood obesity.

Early onset of obesity results in above-average growth in mid-childhood, such that over half of overweight children have heights in the 70 - 99 percentile range at around 10 years of age. The adult heights achieved by these children are what would be expected from their families because the excess mid-childhood growth is offset by attenuation of the pubertal growth spurt. // A percentile is the value of a variable below which a certain percent of observations fall. ...

Precocious puberty and a variety of conditions associated with excessive amounts of testosterone or estrogen in childhood will result in tallness by mid-childhood. However, the acceleration of bone maturation by the early rise of estradiol results in early completion of growth, and adult heights for these children may actually be below average for genetic potential. Precocious puberty means early puberty. ... Testosterone is a steroid hormone from the androgen group. ... Estriol. ...

Extra sex chromosomes (beyond the normal two) with therefore extra copies of the SHOX gene (beyond the normal two) usually results in enhancement of height growth. The most common of these karyotypes are 47,XXY (Klinefelter syndrome), 47,XYY, and 47,XXX. The added height increment is usually modest. Figure 1: A representation of a condensed eukaryotic chromosome, as seen during cell division. ... Short stature homeobox gene or SHOX is a gene on the X chromosome and Y chromosome which is associated with short stature in humans if mutated or present in only one copy (haploinsufficiency). ... XXY karyotype Klinefelters syndrome is a condition caused by a chromosome abnormality in males (specifically, a nondisjunction); sufferers have a pair of X sex chromosomes instead of just one. ... XYY, or XYY syndrome, is a trisomy of the sex chromosomes in which a human male receives an extra Y chromosome in each cell, hence having a karyotype of 47,XYY. Effects Physical traits XYY syndrome typically causes no unusual physical features or medical problems. ... Triple X syndrome is a chromosomal aneuploid abnormality characterized by the presence of an extra X chromosome in each cell of a human female. ...

Hypogonadism is the condition of deficiency of sex hormones due to reduced function of the testes or ovaries at adolescence. When secretion of testosterone or estradiol remains below average throughout the teenage years, a taller adult height will be gradually achieved by extra growth of the arms and legs. This long-limbed tallness is termed "eunuchoid" tallness, but rarely adds more than 2.5 - 7.5 cm (1-3 inches) to adult height. The extra growth is prevented if the child is given appropriate replacement of testosterone or estrogen from early adolescence. Hypogonadism is a medical term for a defect of the reproductive system which results in lack of function of the gonads (ovaries or testes). ... Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... For ovary as part of plants see ovary (plants) Ovaries are egg-producing reproductive organs found in female organisms. ... OK TEENAGERS ARE VIRGINS “Adolescent” redirects here. ... A separate article is about the punk band called The Adolescents. ... European illustration of a Eunuch (1749) A eunuch is a castrated man; the term usually refers to those castrated in order to perform a specific social function, as was common in many societies of the past. ...

A very rare but more extreme version of "eunuochoid" tallness occurs when a mutation of the estrogen receptor reduces the response of the bones to estradiol. Estradiol is a byproduct of testosterone in both males and females, and is the most potent accelerator of bone maturation and closure known. If a person fails to respond to estrogen, growth can continue until late-20s or longer, and the affected person can reach 8 feet or more in height. Estrogen resistance is the only other endocrine condition that can rival growth hormone excess in producing gigantism. In contrast, the tallness associated with the more common androgen insensitivity syndrome averages only a few inches, as estradiol is not produced directly but rather through conversion from androgens by aromatase. Estradiol (17β-estradiol) (also oestradiol) is a sex hormone. ... Androgen insensitivity syndrome (AIS, or Androgen resistance syndrome) is a set of disorders of sexual differentiation that results from mutations of the gene encoding the androgen receptor. ... Aromatase belongs to the group of cytochrome P450 enzymes (EC 1. ...

Marfan syndrome is an uncommon genetic disease due to an inherited defect of connective tissue. In addition to moderate tallness, persons with this condition usually have a slender body build with unusually long fingers (arachnodactyly). Many can also develop a dislocaton of the lens of the eye or, more seriously, a progressive deterioration of the walls of the aorta which can result in sudden death in adulthood. It is usually inherited as an autosomal dominant trait. Marfan syndrome is an autosomal dominant genetic disorder of the connective tissue characterized by disproportionately long limbs, long thin fingers, a relatively tall stature, and a predisposition to cardiovascular abnormalities, specifically those affecting the heart valves and aorta. ... The aorta (generally pronounced or ay-orta) is the largest artery in the human body, originating from the left ventricle of the heart and bringing oxygenated blood to all parts of the body in the systemic circulation. ...

Sotos syndrome resembles acromegaly in its mild distortion of facial growth. In addition to tallness, the chief characteristics are large head size, slow development, and autosomal-dominant inheritance. Sotos syndrome (also known as cerebral gigantism) is a rare genetic disorder characterized by excessive physical growth during the first 2 to 3 years of life. ...

There are about 50 even rarer genetic syndromes in which childhood growth is above average. These conditions are often associated with developmental delay or other more serious problems, and adult height may or may not be mildly increased.

Etymology and terminology

Other names somewhat obsolete for this pathology are hypersomia (Greek: hyper over the normal level; soma body)and somatomegaly (Greek; soma body, object pronoun somatos of the body; megas, megalos great).

See also

• Acromegaly
• Deep-sea gigantism
• Growth hormone
• Island gigantism
• List of people with gigantism
• Local gigantism
• Megafauna

Acromegaly (from Greek akros high and megas large - extremities enlargement) is a hormonal disorder that results when the pituitary gland produces excess growth hormone (hGH). ... A Giant isopod (Bathynomus giganteus) In zoology, deep-sea gigantism, also known as abyssal gigantism, is the tendency for species of crustaceans, invertebrates and other deep-sea dwelling animals to display a larger size than their shallow-water counterparts. ... Growth hormone (GH or somatotropin) is a 191-amino acid, single chain polypeptide hormone which is synthesised, stored and secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland, which stimulates growth and cell reproduction in humans and other animals. ... Island gigantism is a biological phenomenon by which the size of animals isolated on an island increases dramatically over generations. ... This is a list of notable people who have or had a form of gigantism. ... local gigantism of 2nd toe in a child Local gigantism or localised gigantism is a condition in which a certain part of the body acquires larger than normal size due to excessive growth of the anatomical structures or abnormal accumulation of substances. ... The mammoth, an extinct genus of megafauna. ...

References

External links

• Acromegaly and Gigantism (very comprehensive article)
• Acromegaly and Gigantism (Image of a patient with macroglossia - enlargement of the tongue)
• Brief overview of overgrowth syndromes in childhoodPDF (2.95 MiB)
• Hoax of Extremely Large Giants Exposed as Untrue