Disease at a Glance
Summary
Gigantism is abnormally large growth due to an excess of growth hormone (GH) during childhood, before the bone growth plates have closed (epiphyseal fusion). It causes excessive growth in height, muscles, and organs, making the child extremely large for his or her age. Other symptoms may include delayed puberty; double vision or difficulty with side (peripheral) vision; prominent forehead (frontal bossing) and a prominent jaw; headache; increased sweating (hyperhidrosis); irregular periods; large hands and feet with thick fingers and toes; thickening of the facial features; and weakness. It may begin at any age before epiphyseal fusion. The most common cause is a non-cancerous (benign) tumor of the pituitary gland, which may cause it to make too much GH, but it can be caused by other underlying conditions (which may cause a pituitary tumor) including Carney complex; McCune-Albright syndrome ; Multiple endocrine neoplasia type 1 (MEN-1) and type 4; and Neurofibromatosis. In some cases the disease is caused by genetic changes in the GPR101 gene.
Estimated Number of People with this Disease
This section is currently in development.
What Information Does GARD Have For This Disease?
Many rare diseases have limited information. Currently GARD is able to provide the following information for this disease:
*Data may be currently unavailable to GARD at this time.
Categories
When do symptoms of this disease begin?
The most common ages for symptoms of a disease to begin is called age of onset. Age of onset can vary for different diseases and may be used by a doctor to determine the diagnosis. For some diseases, symptoms may begin in a single age range or several age ranges. For other diseases, symptoms may begin any time during a person's life.
Prenatal
Before Birth
Newborn
Birth-4 weeks
Infant Selected
1-23 months
Child Selected
2-11 years
Adolescent Selected
12-18 years
Adult
19-65 years
Older Adult
65+ years
The common ages for symptoms to begin in this disease are shown above by the colored icon(s).
Symptoms
These symptoms may be different from person to person. Some people may have more symptoms than others and symptoms can range from mild to severe. This list does not include every symptom.
This disease might cause these symptoms:
This disease might cause these symptoms:
Musculoskeletal System
19 Symptoms
Tile View
List View
Musculoskeletal System
The musculoskeletal system is made up of the bones, muscles, and joints. Common symptoms of problems in the musculoskeletal system include pain, weakness, stiffness, noises in the joints, inflammation, and decreased range of motion. Diseases affecting the musculoskeletal system may be diagnosed and treated by an orthopedist, rheumatologist, or neuromuscular specialist.
19 Symptoms
Causes
Genetic Disease
Gigantism is a genetic disease, which means that it is caused by one or more genes not working correctly.
The following gene(s) are known to be associated with this disease: AIP, MEN1
Questions:
What is a gene?
Genes are part of our DNA, the basic genetic material found in each of our body's cells. Cells are the building blocks of all living things and specialized cells form our body's organs and tissues. DNA is found in the nucleus of a cell and, in humans, is packaged into 23 pairs of chromosomes with the help of special proteins.
Each gene performs a different job in our cells. Some genes serve as the instructions to make proteins. Proteins are needed for the structure, function, and regulation of the body's cells, tissues, and organs. Some genes can turn other genes on or off. Others make RNA molecules that are involved in chemical reactions in the body.
Sources to Learn More: What is a gene? (MedlinePlus) ; What's a Gene? (NHGRI) ; What are proteins and what do they do? (MedlinePlus)Genes are part of our DNA, the basic genetic material found in each of our body's cells. Cells are the building blocks of all living things and specialized cells form our body's organs and tissues. DNA is found in the nucleus of a cell and, in humans, is packaged into 23 pairs of chromosomes with the help of special proteins.
Each gene performs a different job in our cells. Some genes serve as the instructions to make proteins. Proteins are needed for the structure, function, and regulation of the body's cells, tissues, and organs. Some genes can turn other genes on or off. Others make RNA molecules that are involved in chemical reactions in the body.
Sources to Learn More: What is a gene? (MedlinePlus) ; What's a Gene? (NHGRI) ; What are proteins and what do they do? (MedlinePlus)
Each gene performs a different job in our cells. Some genes serve as the instructions to make proteins. Proteins are needed for the structure, function, and regulation of the body's cells, tissues, and organs. Some genes can turn other genes on or off. Others make RNA molecules that are involved in chemical reactions in the body.
Sources to Learn More: What is a gene? (MedlinePlus) ; What's a Gene? (NHGRI) ; What are proteins and what do they do? (MedlinePlus)Genes are part of our DNA, the basic genetic material found in each of our body's cells. Cells are the building blocks of all living things and specialized cells form our body's organs and tissues. DNA is found in the nucleus of a cell and, in humans, is packaged into 23 pairs of chromosomes with the help of special proteins.
Each gene performs a different job in our cells. Some genes serve as the instructions to make proteins. Proteins are needed for the structure, function, and regulation of the body's cells, tissues, and organs. Some genes can turn other genes on or off. Others make RNA molecules that are involved in chemical reactions in the body.
Sources to Learn More: What is a gene? (MedlinePlus) ; What's a Gene? (NHGRI) ; What are proteins and what do they do? (MedlinePlus)
What is a genetic variant?
A genetic variant is a change in a gene's code or DNA sequence that causes the gene to be different than found in most people. A benign variant does not cause health problems or disease because the change does not affect how the gene works. A pathogenic variant does cause health problems or disease because the change does affect how the gene works. A pathogenic variant may also be called a mutation or a disease-causing variant.
Variants can result from DNA copying mistakes made during cell division or certain environmental exposures. Variants that occur in the egg or sperm (germline mutations) can be passed on to offspring, while variants that occur in other body cells (somatic mutations) are not passed on.
Sources to Learn More: What is a genetic variant and how do variants occur? (MedlinePlus); Definition of Variant (NCI); Mutation definition, illustration, and related terms (NHGRI)A genetic variant is a change in a gene's code or DNA sequence that causes the gene to be different than found in most people. A benign variant does not cause health problems or disease because the change does not affect how the gene works. A pathogenic variant does cause health problems or disease because the change does affect how the gene works. A pathogenic variant may also be called a mutation or a disease-causing variant.
Variants can result from DNA copying mistakes made during cell division or certain environmental exposures. Variants that occur in the egg or sperm (germline mutations) can be passed on to offspring, while variants that occur in other body cells (somatic mutations) are not passed on.
Sources to Learn More: What is a genetic variant and how do variants occur? (MedlinePlus); Definition of Variant (NCI); Mutation definition, illustration, and related terms (NHGRI)
Variants can result from DNA copying mistakes made during cell division or certain environmental exposures. Variants that occur in the egg or sperm (germline mutations) can be passed on to offspring, while variants that occur in other body cells (somatic mutations) are not passed on.
Sources to Learn More: What is a genetic variant and how do variants occur? (MedlinePlus); Definition of Variant (NCI); Mutation definition, illustration, and related terms (NHGRI)A genetic variant is a change in a gene's code or DNA sequence that causes the gene to be different than found in most people. A benign variant does not cause health problems or disease because the change does not affect how the gene works. A pathogenic variant does cause health problems or disease because the change does affect how the gene works. A pathogenic variant may also be called a mutation or a disease-causing variant.
Variants can result from DNA copying mistakes made during cell division or certain environmental exposures. Variants that occur in the egg or sperm (germline mutations) can be passed on to offspring, while variants that occur in other body cells (somatic mutations) are not passed on.
Sources to Learn More: What is a genetic variant and how do variants occur? (MedlinePlus); Definition of Variant (NCI); Mutation definition, illustration, and related terms (NHGRI)
What is a genetic disease?
A genetic disease is a disease caused by a change in part of a person's DNA. Genetic diseases may be caused by genetic changes in a single gene, in multiple genes, by a combination of genetic changes and environmental factors (multifactorial inheritance), or changes in chromosomes.
Genetic diseases may be caused by genetic changes that are inherited from the parents and are present at birth, like sickle cell disease. Other genetic diseases present at birth may be caused by random genetic changes that happen while the egg or the sperm is forming or soon after fertilization.
Some diseases, like many cancers, are caused by genetic changes that happen during a person's life. These are known as acquired or somatic cell genetic changes. Such genetic changes are not inherited from a parent, but happen either randomly or due to some environmental exposure (such as cigarette smoke).
Sources to Learn More: Genetic Disorders (MedlinePlus) ; Genetic Disorders (NHGRI)A genetic disease is a disease caused by a change in part of a person's DNA. Genetic diseases may be caused by genetic changes in a single gene, in multiple genes, by a combination of genetic changes and environmental factors (multifactorial inheritance), or changes in chromosomes.
Genetic diseases may be caused by genetic changes that are inherited from the parents and are present at birth, like sickle cell disease. Other genetic diseases present at birth may be caused by random genetic changes that happen while the egg or the sperm is forming or soon after fertilization.
Some diseases, like many cancers, are caused by genetic changes that happen during a person's life. These are known as acquired or somatic cell genetic changes. Such genetic changes are not inherited from a parent, but happen either randomly or due to some environmental exposure (such as cigarette smoke).
Sources to Learn More: Genetic Disorders (MedlinePlus) ; Genetic Disorders (NHGRI)
Genetic diseases may be caused by genetic changes that are inherited from the parents and are present at birth, like sickle cell disease. Other genetic diseases present at birth may be caused by random genetic changes that happen while the egg or the sperm is forming or soon after fertilization.
Some diseases, like many cancers, are caused by genetic changes that happen during a person's life. These are known as acquired or somatic cell genetic changes. Such genetic changes are not inherited from a parent, but happen either randomly or due to some environmental exposure (such as cigarette smoke).
Sources to Learn More: Genetic Disorders (MedlinePlus) ; Genetic Disorders (NHGRI)A genetic disease is a disease caused by a change in part of a person's DNA. Genetic diseases may be caused by genetic changes in a single gene, in multiple genes, by a combination of genetic changes and environmental factors (multifactorial inheritance), or changes in chromosomes.
Genetic diseases may be caused by genetic changes that are inherited from the parents and are present at birth, like sickle cell disease. Other genetic diseases present at birth may be caused by random genetic changes that happen while the egg or the sperm is forming or soon after fertilization.
Some diseases, like many cancers, are caused by genetic changes that happen during a person's life. These are known as acquired or somatic cell genetic changes. Such genetic changes are not inherited from a parent, but happen either randomly or due to some environmental exposure (such as cigarette smoke).
Sources to Learn More: Genetic Disorders (MedlinePlus) ; Genetic Disorders (NHGRI)
Inheritance
All individuals inherit two copies of most genes. The number of copies of a gene that need to have a disease-causing variant affects the way a disease is inherited. This disease is inherited in the following pattern(s):
Questions:
Autosomal dominant inheritance
Autosomal means the gene is located on any chromosome except the X or Y chromosomes (sex chromosomes). Genes, like chromosomes, usually come in pairs. Dominant means that only one copy of the responsible gene (causal gene) must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
In some cases, a person inherits the pathogenic variant from a parent who has the genetic disease. In other cases, the disease occurs because of a new pathogenic variant (de novo) in the causal gene and there is no family history of the disease.
Each child of an individual with an autosomal dominant disease has a 50% (1 in 2) chance of inheriting the variant and the disease. Typically, children who inherit a dominant variant will have the disease, but they may be more or less severely impacted than their parent. Sometimes a person may have a pathogenic variant for an autosomal dominant disease and show no signs or symptoms of the disease.Autosomal means the gene is located on any chromosome except the X or Y chromosomes (sex chromosomes). Genes, like chromosomes, usually come in pairs. Dominant means that only one copy of the responsible gene (causal gene) must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
In some cases, a person inherits the pathogenic variant from a parent who has the genetic disease. In other cases, the disease occurs because of a new pathogenic variant (de novo) in the causal gene and there is no family history of the disease.
Each child of an individual with an autosomal dominant disease has a 50% (1 in 2) chance of inheriting the variant and the disease. Typically, children who inherit a dominant variant will have the disease, but they may be more or less severely impacted than their parent. Sometimes a person may have a pathogenic variant for an autosomal dominant disease and show no signs or symptoms of the disease.
In some cases, a person inherits the pathogenic variant from a parent who has the genetic disease. In other cases, the disease occurs because of a new pathogenic variant (de novo) in the causal gene and there is no family history of the disease.
Each child of an individual with an autosomal dominant disease has a 50% (1 in 2) chance of inheriting the variant and the disease. Typically, children who inherit a dominant variant will have the disease, but they may be more or less severely impacted than their parent. Sometimes a person may have a pathogenic variant for an autosomal dominant disease and show no signs or symptoms of the disease.Autosomal means the gene is located on any chromosome except the X or Y chromosomes (sex chromosomes). Genes, like chromosomes, usually come in pairs. Dominant means that only one copy of the responsible gene (causal gene) must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
In some cases, a person inherits the pathogenic variant from a parent who has the genetic disease. In other cases, the disease occurs because of a new pathogenic variant (de novo) in the causal gene and there is no family history of the disease.
Each child of an individual with an autosomal dominant disease has a 50% (1 in 2) chance of inheriting the variant and the disease. Typically, children who inherit a dominant variant will have the disease, but they may be more or less severely impacted than their parent. Sometimes a person may have a pathogenic variant for an autosomal dominant disease and show no signs or symptoms of the disease.
X-linked inheritance
X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. X-linked diseases are caused by disease-causing (pathogenic) variants in genes on the X chromosome. Mutation is an older term that is still sometimes used to mean pathogenic variant.
The inheritance pattern of many X-linked diseases is not clearly dominant or recessive and so the pattern may be stated as X-linked inheritance. Because men have only one copy of genes on the X chromosome, a pathogenic variant in one copy can cause the disease. Women who have a pathogenic variant in one copy of the gene usually have less severe symptoms than males who have the disease or may have no symptoms at all. Women who have pathogenic variants in both copies of the gene would have symptoms similar to men.
A woman who carries one X-linked pathogenic variant has a 50% (1 in 2) chance of having a son or daughter who has a pathogenic variant in one copy of the gene. A man with an X-linked disease cannot pass on the disease to his sons, but all of his daughters will have a pathogenic variant in one copy of the gene. If a child is the first person in a family with the disease, the pathogenic variant may have been inherited from the mother who did not have symptoms or may have occurred by chance for the first time in the child (de novo).X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. X-linked diseases are caused by disease-causing (pathogenic) variants in genes on the X chromosome. Mutation is an older term that is still sometimes used to mean pathogenic variant.
The inheritance pattern of many X-linked diseases is not clearly dominant or recessive and so the pattern may be stated as X-linked inheritance. Because men have only one copy of genes on the X chromosome, a pathogenic variant in one copy can cause the disease. Women who have a pathogenic variant in one copy of the gene usually have less severe symptoms than males who have the disease or may have no symptoms at all. Women who have pathogenic variants in both copies of the gene would have symptoms similar to men.
A woman who carries one X-linked pathogenic variant has a 50% (1 in 2) chance of having a son or daughter who has a pathogenic variant in one copy of the gene. A man with an X-linked disease cannot pass on the disease to his sons, but all of his daughters will have a pathogenic variant in one copy of the gene. If a child is the first person in a family with the disease, the pathogenic variant may have been inherited from the mother who did not have symptoms or may have occurred by chance for the first time in the child (de novo).
The inheritance pattern of many X-linked diseases is not clearly dominant or recessive and so the pattern may be stated as X-linked inheritance. Because men have only one copy of genes on the X chromosome, a pathogenic variant in one copy can cause the disease. Women who have a pathogenic variant in one copy of the gene usually have less severe symptoms than males who have the disease or may have no symptoms at all. Women who have pathogenic variants in both copies of the gene would have symptoms similar to men.
A woman who carries one X-linked pathogenic variant has a 50% (1 in 2) chance of having a son or daughter who has a pathogenic variant in one copy of the gene. A man with an X-linked disease cannot pass on the disease to his sons, but all of his daughters will have a pathogenic variant in one copy of the gene. If a child is the first person in a family with the disease, the pathogenic variant may have been inherited from the mother who did not have symptoms or may have occurred by chance for the first time in the child (de novo).X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. X-linked diseases are caused by disease-causing (pathogenic) variants in genes on the X chromosome. Mutation is an older term that is still sometimes used to mean pathogenic variant.
The inheritance pattern of many X-linked diseases is not clearly dominant or recessive and so the pattern may be stated as X-linked inheritance. Because men have only one copy of genes on the X chromosome, a pathogenic variant in one copy can cause the disease. Women who have a pathogenic variant in one copy of the gene usually have less severe symptoms than males who have the disease or may have no symptoms at all. Women who have pathogenic variants in both copies of the gene would have symptoms similar to men.
A woman who carries one X-linked pathogenic variant has a 50% (1 in 2) chance of having a son or daughter who has a pathogenic variant in one copy of the gene. A man with an X-linked disease cannot pass on the disease to his sons, but all of his daughters will have a pathogenic variant in one copy of the gene. If a child is the first person in a family with the disease, the pathogenic variant may have been inherited from the mother who did not have symptoms or may have occurred by chance for the first time in the child (de novo).
X-linked dominant inheritance
X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. Dominant means that when there are two copies of the responsible gene, only one copy must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
Because women have two X chromosomes, a pathogenic variant for an X-lined dominant disease needs to occur in only one copy of the gene to cause the disease. Because men have one X chromosome and thus only one copy of the gene, a pathogenic variant in their one copy is enough to cause the disease. Women may experience less severe symptoms than men.
A woman who carries one X-linked gene variant has a 50% (1 in 2) chance of having a son or daughter with the disease. A man with an X-linked dominant disease cannot pass on the disease to his sons, but all of his daughters will have the disease. If a child is the first person in a family with the disease, the pathogenic variant may have occurred by chance for the first time in the child (de novo).X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. Dominant means that when there are two copies of the responsible gene, only one copy must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
Because women have two X chromosomes, a pathogenic variant for an X-lined dominant disease needs to occur in only one copy of the gene to cause the disease. Because men have one X chromosome and thus only one copy of the gene, a pathogenic variant in their one copy is enough to cause the disease. Women may experience less severe symptoms than men.
A woman who carries one X-linked gene variant has a 50% (1 in 2) chance of having a son or daughter with the disease. A man with an X-linked dominant disease cannot pass on the disease to his sons, but all of his daughters will have the disease. If a child is the first person in a family with the disease, the pathogenic variant may have occurred by chance for the first time in the child (de novo).
Because women have two X chromosomes, a pathogenic variant for an X-lined dominant disease needs to occur in only one copy of the gene to cause the disease. Because men have one X chromosome and thus only one copy of the gene, a pathogenic variant in their one copy is enough to cause the disease. Women may experience less severe symptoms than men.
A woman who carries one X-linked gene variant has a 50% (1 in 2) chance of having a son or daughter with the disease. A man with an X-linked dominant disease cannot pass on the disease to his sons, but all of his daughters will have the disease. If a child is the first person in a family with the disease, the pathogenic variant may have occurred by chance for the first time in the child (de novo).X-linked means the gene is located on the X chromosome, one of two sex chromosomes. Genes, like chromosomes, usually come in pairs. Dominant means that when there are two copies of the responsible gene, only one copy must have a disease-causing change (pathogenic variant) in order for a person to have the disease. Mutation is an older term that is still sometimes used to mean pathogenic variant.
Because women have two X chromosomes, a pathogenic variant for an X-lined dominant disease needs to occur in only one copy of the gene to cause the disease. Because men have one X chromosome and thus only one copy of the gene, a pathogenic variant in their one copy is enough to cause the disease. Women may experience less severe symptoms than men.
A woman who carries one X-linked gene variant has a 50% (1 in 2) chance of having a son or daughter with the disease. A man with an X-linked dominant disease cannot pass on the disease to his sons, but all of his daughters will have the disease. If a child is the first person in a family with the disease, the pathogenic variant may have occurred by chance for the first time in the child (de novo).
Next Steps
Talking with the Medical Team
Good communication between the patient, family, and medical team can lead to an accurate diagnosis. In addition, health care decisions can be made together which improves the patient’s well-being and quality of life.
The National Library of Medicine's Unified Medical Language System (UMLS) is used to classify and organize diseases and disease categories.
Data from Orphanet and Human Phenotype Ontology (HPO) are used to provide information on a disease's symptoms, genes, inheritance, population estimates, and more.
National Academies of Sciences, Engineering, and Medicine. 2015. Improving Diagnosis in Health Care. Washington, DC: The National Academies Press.
U.S. Department of Health and Human Services, Office of Disease Prevention and Health Promotion. (2015). Health Literacy Online: A Guide for Simplifying the User Experience.
- Reference: Access aggregated data from Orphanet at Orphadata. Orphanet is an online database of rare diseases and orphan drugs. Copyright, INSERM 1997.
- Reference: Download data from HPO. Kohler S, Gargano M, Matentzoglu N, et al., The Human Phenotype Ontology in 2021, Nucleic Acids Research, Volume 49, Issue D1, 8 January 2021, Pages D1207–D1217.
- Reference: MedGen Data Downloads and FTP
- Reference: Data from the Newborn Screening Coding and Terminology Guide is available here. Downs SM, van Dyck PC, Rinaldo P, et al. Improving newborn screening laboratory test ordering and result reporting using health information exchange . J Am Med Inform Assoc. 2010 Jan-Feb;17(1):13-8.
National Academies of Sciences, Engineering, and Medicine. 2015. Improving Diagnosis in Health Care. Washington, DC: The National Academies Press.
U.S. Department of Health and Human Services, Office of Disease Prevention and Health Promotion. (2015). Health Literacy Online: A Guide for Simplifying the User Experience.
Last Updated: Nov. 8, 2021