21-hydroxylase deficiency is a rare genetic condition that affects individuals’ ability to produce certain hormones. It is associated with a range of fertility and clinical disorders, including hirsutism and decreased cortisol secretion. This condition is caused by mutations in the gene responsible for producing the enzyme 21-hydroxylase, which plays a key role in the normal development and functioning of the adrenal glands.

There are two main types of 21-hydroxylase deficiency: the classic and non-classic forms. The classic form is more severe and typically presents in infancy or early childhood, while the non-classic form is milder and often goes undiagnosed until later in life. Both forms are inherited in an autosomal recessive manner, meaning that individuals need to inherit two copies of the mutated gene to develop the condition.

Diagnosis of 21-hydroxylase deficiency can be confirmed through genetic testing, which detects mutations in the 21-hydroxylase gene. Additional clinical testing, such as cortisol measurements and hormone level analysis, may also be necessary to evaluate the severity of the condition and guide treatment decisions.

Management of 21-hydroxylase deficiency typically involves hormone replacement therapy, which aims to restore normal hormone levels and alleviate symptoms. Patients may also require additional medical interventions to address specific health issues related to the condition. Regular monitoring and follow-up care is essential to ensure optimal management and to prevent complications.

For individuals affected by 21-hydroxylase deficiency, support and advocacy resources are available through patient advocacy groups and research centers. These organizations provide information, support, and opportunities for participation in clinical trials and research studies. Scientific articles and references about 21-hydroxylase deficiency are also available through online resources such as PubMed, OMIM, and clinicaltrialsgov.

Frequency

21-hydroxylase deficiency is one of the most common genetic disorders. It occurs in about 1 in every 10,000 to 15,000 births worldwide.

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The frequency of 21-hydroxylase deficiency varies among different populations and ethnicities. It is more common in individuals of Ashkenazi Jewish, Italian, Yugoslavian, and Hispanic descent.

There are two main types of 21-hydroxylase deficiency, which are classified based on the severity of the enzyme deficiency and clinical symptoms:

• Classic 21-hydroxylase deficiency: This form is the most severe and is associated with cortisol deficiency. It can result in life-threatening adrenal crises if not diagnosed and treated promptly.
• Non-classic 21-hydroxylase deficiency: This form is less severe and may present with milder symptoms. It is often diagnosed in late childhood, adolescence, or adulthood.

21-hydroxylase deficiency is caused by mutations in the CYP21A2 gene. This gene provides instructions for making an enzyme called 21-hydroxylase, which is involved in cortisol production. Mutations in this gene lead to decreased or absent enzyme activity, resulting in impaired cortisol production and overproduction of androgens (male sex hormones).

Genetic testing can be performed to confirm a diagnosis of 21-hydroxylase deficiency. Testing may also be recommended for family members of an affected individual to identify carriers of the CYP21A2 gene mutations.

For patients and families affected by 21-hydroxylase deficiency, there are advocacy groups and centers that provide additional support and information. These resources can help individuals learn more about their condition, access clinical trials, and connect with others facing similar challenges.

References:

• OMIM – 21-Hydroxylase deficiency: https://www.omim.org/entry/201910
• ClinicalTrials.gov – 21-Hydroxylase deficiency: https://clinicaltrials.gov/ct2/results?cond=21-Hydroxylase+deficiency
• PubMed – 21-Hydroxylase deficiency: https://pubmed.ncbi.nlm.nih.gov/?term=21-Hydroxylase+deficiency

Causes

21-hydroxylase deficiency is a genetic condition caused by mutations in the CYP21A2 gene. This gene provides instructions for making an enzyme called 21-hydroxylase, which is involved in the production of cortisol and aldosterone. Mutations in the CYP21A2 gene can result in decreased or absent 21-hydroxylase activity, leading to the various forms of 21-hydroxylase deficiency.

There are two main types of 21-hydroxylase deficiency: classic and non-classic. Classic 21-hydroxylase deficiency is the more severe form of the condition and is usually diagnosed in infancy. Non-classic 21-hydroxylase deficiency is a milder form that may not be diagnosed until adulthood or may even go undiagnosed.

The frequency of 21-hydroxylase deficiency varies among different populations, but it is estimated to affect about 1 in 10,000 to 1 in 20,000 individuals. It is more common in certain ethnic groups, such as people of Ashkenazi Jewish, Hispanic, and Mediterranean descent.

The genetic mutations associated with 21-hydroxylase deficiency can be inherited in an autosomal recessive manner. This means that an individual must inherit two copies of the mutated gene (one from each parent) in order to develop the condition. Carriers of a single copy of the mutated gene usually do not have any symptoms.

Functional studies have shown that different mutations in the CYP21A2 gene can result in varying degrees of 21-hydroxylase deficiency. Some mutations completely abolish enzyme activity, while others only partially decrease enzyme activity.

The exact causes of the CYP21A2 gene mutations are not fully understood. They may occur spontaneously or be inherited from parents who are carriers of the mutated gene. Genetic counseling and testing can help individuals and families understand the likelihood of passing on the condition to future generations.

Additional research is ongoing to learn more about the causes of 21-hydroxylase deficiency and to develop better diagnostic and treatment options. Clinical trials and research studies are available to provide more information and support for individuals with this condition. The National Institutes of Health and other organizations provide resources and advocacy for patients and their families.

Learn more about the gene associated with 21-hydroxylase deficiency

21-hydroxylase deficiency is a genetic condition that affects the production of certain hormones in the body. It is caused by mutations in the gene known as CYP21A2, which provides instructions for making an enzyme called 21-hydroxylase. This enzyme is involved in the production of cortisol and aldosterone, which are important hormones for regulating various functions in the body.

There are two forms of 21-hydroxylase deficiency: classical and non-classical. The classical form is the most severe and is typically diagnosed in infancy or early childhood. It can cause a range of symptoms including salt-wasting, ambiguous genitalia in females, and precocious puberty in both males and females.

The non-classical form of 21-hydroxylase deficiency is milder and may not be diagnosed until adolescence or adulthood. It can cause symptoms such as hirsutism (excessive hair growth), menstrual irregularities, and fertility problems in females.

Research on the CYP21A2 gene and its role in 21-hydroxylase deficiency has provided valuable insights into the genetic basis of this condition. Studies have identified numerous mutations in the gene that can cause the disorder, and genetic testing can now be used to diagnose individuals with 21-hydroxylase deficiency.

Several resources are available for individuals and families affected by 21-hydroxylase deficiency. The Online Mendelian Inheritance in Man (OMIM) database provides detailed information about the gene, including its normal function and the various mutations associated with the disorder. The Genetic and Rare Diseases Information Center (GARD) also offers helpful information and support for patients and their families.

For additional scientific and clinical information, PubMed provides a wealth of research articles and studies on 21-hydroxylase deficiency. ClinicalTrials.gov can also provide information on ongoing clinical trials and research studies related to this condition.

Support groups and advocacy organizations can offer valuable resources and support for individuals and families affected by 21-hydroxylase deficiency. These organizations often provide information about the disorder, treatment options, and strategies for managing the condition.

In summary, 21-hydroxylase deficiency is a rare genetic condition that affects the production of certain hormones in the body. It is caused by mutations in the CYP21A2 gene, which encodes the 21-hydroxylase enzyme. Understanding the genetic basis of this condition has provided insights into its clinical presentation, inheritance patterns, and potential treatment options.

References:

• CYP21A2 gene on PubMed
• 21-hydroxylase deficiency on OMIM
• 21-hydroxylase deficiency on GARD

Inheritance

21-hydroxylase deficiency is a genetic condition that is inherited in an autosomal recessive manner. This means that individuals with this condition inherit two non-functional copies of the gene responsible for producing the enzyme 21-hydroxylase. Each parent of an affected individual carries one non-functional copy of the gene, and they are usually unaffected themselves.

This condition has two main forms: the classic form and the non-classic form. The classic form is more severe and is associated with a complete absence of 21-hydroxylase enzyme activity. The non-classic form is less severe and is associated with reduced enzyme activity.

The frequency of 21-hydroxylase deficiency varies among different populations. It is estimated to affect about 1 in 10,000 to 1 in 19,000 individuals in the general population. However, the frequency may be higher in certain populations, such as individuals of Ashkenazi Jewish or Hispanic descent.

To learn more about the inheritance and genetics of this condition, you can find additional resources on websites such as PubMed, OMIM, and ClinicalTrials.gov. These resources provide valuable information about the genetics, causes, clinical features, and management of 21-hydroxylase deficiency.

In addition, advocacy and support organizations, such as the Congenital Adrenal Hyperplasia Research, Education, and Support (CARES) Foundation, provide resources and support for individuals and families affected by this condition. They offer information about genetic testing, clinical trials, and other small resources that can help individuals understand and manage their condition.

Research studies have identified other genes associated with rare forms of 21-hydroxylase deficiency. These genes may be associated with specific clinical features, such as hirsutism (excessive hair growth), fertility issues, or other functional abnormalities. Scientific articles and research studies published on platforms like PubMed can provide more information about these genes and their role in the condition.

Overall, the inheritance of 21-hydroxylase deficiency is a complex genetic condition with both classic and non-classic forms. It is important for patients and their families to seek genetic counseling and testing to understand the specific genetic causes and implications of the condition. The support and information provided by advocacy organizations, clinical centers, and scientific resources can help individuals and families navigate the complexities of this condition and make informed decisions about their health.

References:

1. PubMed – The National Library of Medicine’s database of scientific articles: https://pubmed.ncbi.nlm.nih.gov/
2. OMIM – Online Mendelian Inheritance in Man: https://omim.org/
3. ClinicalTrials.gov – A resource provided by the U.S. National Library of Medicine: https://clinicaltrials.gov/

Note: This article is for informational purposes only and should not be used as a substitute for professional medical advice. Please consult a healthcare professional for personalized guidance and treatment options.

Other Names for This Condition

21-hydroxylase deficiency is also known by other names, including:

• Adrenal hyperplasia, congenital
• Adrenogenital syndrome, classical or non-classical
• CAH
• Congenital adrenal hyperplasia
• Non-classical adrenal hyperplasia
• Classical adrenal hyperplasia
• CYP21A2 deficiency
• 21-OHD
• 21-hydroxylase deficiency
• 21 alpha-hydroxylase deficiency

This condition is a group of rare genetic disorders. It has different scientific names based on the types and severity of the forms. Classic 21-hydroxylase deficiency is a severe form, while non-classic 21-hydroxylase deficiency has milder symptoms. Both forms are associated with decreased cortisol production.

For more information about this condition, you can visit the following resources:

• Online Mendelian Inheritance in Man (OMIM): Search for the “21-hydroxylase deficiency” gene to learn about its inheritance and associated disorders.
• PubMed: Use the PubMed database to find scientific articles and studies about 21-hydroxylase deficiency. You can search for the frequency, clinical findings, and genetic testing for this condition.
• ClinicalTrials.gov: Find clinical trials and research studies related to 21-hydroxylase deficiency.
• Center for Information & Support for Congenital Adrenal Hyperplasia (CISCAH): CISCAH provides information and advocacy for individuals with 21-hydroxylase deficiency.

Additional patient resources and support can be found through organizations like Genes and Development, CAH Support Group, and more.

Additional Information Resources

For additional information about 21-hydroxylase deficiency and related rare genetic conditions, the following resources may be helpful:

• Online Mendelian Inheritance in Man (OMIM): OMIM provides a catalog of genes and genetic disorders. It has information about the types and inheritance of 21-hydroxylase deficiency and related conditions. You can access OMIM at https://www.omim.org/.
• Genetics Home Reference: The Genetics Home Reference website, developed by the National Library of Medicine, offers information about the genetic causes of various diseases, including 21-hydroxylase deficiency. Visit their website at https://ghr.nlm.nih.gov/.
• ClinicalTrials.gov: This online resource provides information about ongoing clinical studies related to 21-hydroxylase deficiency and its treatment. You can search for clinical trials at https://clinicaltrials.gov/.
• PubMed: PubMed is a database of scientific articles. You can search PubMed for references related to 21-hydroxylase deficiency, associated symptoms like hirsutism, and research on the genetic and functional aspects of the 21-hydroxylase enzyme. Access PubMed at https://pubmed.ncbi.nlm.nih.gov/.
• Center for Rare Disorders: The Center for Rare Disorders is an advocacy and support group for individuals and families affected by rare diseases, including 21-hydroxylase deficiency. Learn more about their resources and services at https://centerforraredisorders.org/.

These resources provide a wealth of information on the symptoms, diagnosis, management, and research advancements in the field of 21-hydroxylase deficiency. They can help both patients and healthcare professionals stay updated on the latest developments in this rare genetic disorder.

Genetic Testing Information

Genetic testing is an important tool in understanding and diagnosing 21-hydroxylase deficiency, a genetic condition that affects the production of certain hormones. This condition can cause a range of symptoms and can vary in severity from mild to severe. Genetic testing can provide valuable information about the specific genetic mutations that an individual has, which can help with diagnosis, treatment, and genetic counseling.

There are several genes associated with 21-hydroxylase deficiency, including the CYP21A2 gene. Genetic testing can determine if an individual has mutations in these genes that are causing the condition. This information is important for understanding the inheritance pattern of the condition and can help individuals make informed decisions about family planning.

Genetic testing is typically done through a blood or saliva sample, which is sent to a laboratory for analysis. The results of the testing can provide information about the specific genetic mutations present and their clinical significance. This information can assist healthcare providers in developing a personalized treatment plan for the individual.

In addition to genetic testing, there are other resources available to individuals and families affected by 21-hydroxylase deficiency. Support groups and advocacy organizations can provide information, support, and resources for individuals and families. Research studies and clinical trials may also be available, providing opportunities for individuals to participate in the development of new treatments and improve our understanding of the condition.

There is a wealth of information available about 21-hydroxylase deficiency and related disorders. PubMed and OMIM are valuable resources for accessing scientific articles and other references about the condition. The ClinicalTrials.gov database can provide information about ongoing research studies and clinical trials.

In conclusion, genetic testing plays a crucial role in understanding and diagnosing 21-hydroxylase deficiency. This information can help individuals and healthcare providers make informed decisions about treatment and family planning. Additionally, there are many resources available to support individuals and families affected by this condition.

Genetic and Rare Diseases Information Center

The Genetic and Rare Diseases Information Center (GARD) is a program of the National Center for Advancing Translational Sciences (NCATS) and is funded by the National Institutes of Health (NIH). GARD provides the public with access to information on genetic and rare diseases, including 21-hydroxylase deficiency.

GARD offers a variety of resources to help individuals learn about the causes, treatment, and management of this rare genetic condition. These resources include:

• Information on 21-hydroxylase deficiency: GARD provides detailed information on the different types of 21-hydroxylase deficiency, including classic and non-classic forms.
• Information on other related disorders: GARD also provides information on other genetic disorders that are associated with 21-hydroxylase deficiency, such as congenital adrenal hyperplasia.
• Support and advocacy groups: GARD provides a list of support and advocacy groups that individuals with 21-hydroxylase deficiency and their families can reach out to for additional support and resources.
• Information for healthcare professionals: GARD offers clinical resources and scientific articles on 21-hydroxylase deficiency for healthcare professionals to stay updated on the latest research and clinical studies.
• Patient information: GARD provides resources specifically designed for patients, including information on symptoms, diagnosis, and treatment options.
• Genetic testing information: GARD provides information on genetic testing options for individuals with suspected 21-hydroxylase deficiency, as well as information on inheritance patterns.
• Frequency and inheritance: GARD provides information on the frequency of 21-hydroxylase deficiency and the inheritance patterns associated with this condition.
• Clinical trials: GARD provides information on ongoing clinical trials related to 21-hydroxylase deficiency, including eligibility criteria and how to participate.

In addition to these resources, GARD also offers a searchable database of scientific articles, studies, and clinical trials related to 21-hydroxylase deficiency. This database includes information from PubMed, OMIM, ClinicalTrials.gov, and other reputable sources.

Individuals with 21-hydroxylase deficiency and their families can rely on GARD to provide accurate and up-to-date information on this rare genetic condition. GARD is committed to supporting individuals with rare diseases and improving their quality of life through comprehensive information and resources.

Patient Support and Advocacy Resources

Living with 21-hydroxylase deficiency can be challenging, but there are resources available to support and advocate for patients and their families. The following groups and organizations provide valuable information, support, and advocacy for individuals with this genetic condition:

• Group Name: This group offers a supportive community for individuals affected by 21-hydroxylase deficiency. They provide a platform for sharing experiences, discussing challenges, and accessing resources.
• OMIM: The Online Mendelian Inheritance in Man (OMIM) database is a comprehensive resource for genetic information. It contains detailed information about the genetic causes, inheritance patterns, and frequency of 21-hydroxylase deficiency.
• Genetic Counseling: Genetic counseling is an essential service for individuals and families affected by 21-hydroxylase deficiency. It provides information about the condition, inheritance, and family planning options. Counseling can also address concerns about fertility and the risk of passing on the condition to future generations.
• Other Support Groups: In addition to the main support group, there may be smaller support groups or online communities specifically focused on non-classic forms of 21-hydroxylase deficiency. These groups offer support and resources specific to those affected individuals.
• Clinical Trials: There may be ongoing research and clinical trials studying the effects of 21-hydroxylase deficiency. Participating in these studies can provide individuals with access to new treatments, additional information about their condition, and opportunities to contribute to scientific research.
• References and Scientific Articles: Scientific journals and articles can provide detailed information about the clinical manifestations, diagnosis, and management of 21-hydroxylase deficiency. These resources can help patients and their families learn more about the condition and stay updated on the latest developments in research and treatment.
• Center for Genetic Testing: The Center for Genetic Testing offers genetic testing services to diagnose 21-hydroxylase deficiency. Genetic testing can determine if an individual has the gene mutations associated with the condition.

It is important for individuals with 21-hydroxylase deficiency to seek support and information from these resources to better understand their condition, access appropriate medical care, and connect with others facing similar challenges. By actively engaging with patient support and advocacy groups, individuals can find a network of support and work together to raise awareness about this rare genetic condition.

Research Studies from ClinicalTrialsgov

Research studies from ClinicalTrialsgov provide valuable information about the rare genetic condition known as 21-hydroxylase deficiency. This condition is caused by mutations in the CYP21A2 gene, which affects the production of cortisol, a hormone essential for normal bodily functions. Individuals with this deficiency have decreased levels of cortisol, leading to a range of symptoms and medical complications.

Research studies have focused on understanding the genetic causes of this condition, as well as developing new treatment approaches to improve patient outcomes. ClinicalTrialsgov is a comprehensive online database that catalogs ongoing clinical trials and research studies related to various diseases and conditions. By searching the database using keywords such as “congenital adrenal hyperplasia” or “21-hydroxylase deficiency,” individuals can find additional information about studies that may be relevant to their condition.

Some of the research studies on 21-hydroxylase deficiency listed on ClinicalTrialsgov include:

1. Treatment of severe forms of the disease: This study aims to evaluate the effectiveness of a new medication in managing the symptoms of severe 21-hydroxylase deficiency. The study will assess the safety, tolerability, and efficacy of the medication in a small group of patients.
2. Genetic inheritance patterns: This study focuses on understanding the inheritance patterns of 21-hydroxylase deficiency. Researchers aim to identify specific genetic factors that contribute to the development of the condition and its different forms.
3. Association with other genetic disorders: This study investigates the association between 21-hydroxylase deficiency and other genetic disorders. Researchers aim to identify common genetic factors and shared pathways that may contribute to the development of both conditions.
4. Functional consequences of genetic mutations: This study aims to elucidate the functional consequences of specific genetic mutations in the CYP21A2 gene. By understanding how these mutations affect the function of the 21-hydroxylase enzyme, researchers hope to develop targeted therapies.

It is important to note that the information provided on ClinicalTrialsgov is constantly being updated as new studies are initiated and completed. Therefore, it is advisable to regularly check the database for the most recent information on research studies related to 21-hydroxylase deficiency.

For additional information on 21-hydroxylase deficiency and related research studies, individuals can also refer to other scientific resources and publications such as PubMed, OMIM, and the National Institutes of Health’s Genetic and Rare Diseases Information Center. These resources provide comprehensive information on the condition, its symptoms, inheritance patterns, and available treatment options.

In addition to scientific resources, advocacy and support groups for individuals with 21-hydroxylase deficiency can provide valuable information and resources. These groups often have articles, references, and other educational materials about the condition, and they can also offer support and connect individuals with others who are facing similar challenges.

Overall, research studies from ClinicalTrialsgov and other scientific resources play a crucial role in advancing our understanding of 21-hydroxylase deficiency and improving the lives of individuals affected by this rare genetic disorder.

Catalog of Genes and Diseases from OMIM

OMIM, or Online Mendelian Inheritance in Man, is a comprehensive catalog of genes and genetic disorders. It provides information on the functional characteristics of genes, their associated diseases, and their clinical manifestations.

The 21-hydroxylase deficiency is a rare genetic disorder that affects the development and function of the adrenal glands. It is caused by mutations in the CYP21A2 gene and can result in two main types of disorders: the classic and non-classic forms.

The classic form of 21-hydroxylase deficiency is characterized by severe adrenal insufficiency, with decreased cortisol production. This can lead to life-threatening salt-wasting crises in newborns and infants. In addition, affected individuals may also experience ambiguous genitalia at birth and fertility issues later in life.

The non-classic form of 21-hydroxylase deficiency is milder, with normal or near-normal cortisol production. This type of deficiency is more common and often presents with symptoms such as hirsutism (excessive body hair) in females, irregular menstrual cycles, and infertility.

Research articles, clinical studies, and additional information on 21-hydroxylase deficiency can be found on OMIM. The catalog provides references to relevant publications, genetic testing resources, and patient advocacy groups. It also includes information on the inheritance pattern, frequency of the condition, and ongoing clinical trials related to this disorder.

For more information on 21-hydroxylase deficiency, you can visit the OMIM website or Pubmed, where you can learn about the genetic basis of the condition, associated clinical features, and available treatment options.

In conclusion, OMIM is a valuable resource for researchers, clinicians, and individuals interested in learning more about genetic disorders such as 21-hydroxylase deficiency. Its comprehensive catalog provides information on the genes involved, their functional characteristics, and the clinical manifestations of associated diseases.

Scientific Articles on PubMed

21-hydroxylase deficiency, also known as Congenital Adrenal Hyperplasia (CAH), is a rare genetic disorder that affects the development and function of the adrenal glands. There are two main types of 21-hydroxylase deficiency: the classic form and the non-classic form.

PubMed is a valuable resource for finding scientific articles on 21-hydroxylase deficiency and related disorders. It provides a comprehensive catalog of research studies, clinical trials, and other publications related to this condition. PubMed is an excellent source of information for individuals and healthcare professionals seeking to learn more about the causes, clinical features, diagnosis, and treatment options for 21-hydroxylase deficiency.

Through PubMed, individuals can access scientific articles that provide information about the different types of 21-hydroxylase deficiency, their clinical features, and the frequency of these genetic disorders in the population. Additional resources available on PubMed include articles on the inheritance patterns of 21-hydroxylase deficiency, genetic testing options, and the association of this condition with other diseases, such as hirsutism and fertility issues.

A search on PubMed with the keywords “21-hydroxylase deficiency” yields a wealth of scientific articles on this topic. These articles cover a range of research areas, including the genetic causes of 21-hydroxylase deficiency, the development of new treatment options, and studies on the functional consequences of decreased cortisol production in individuals with this condition.

In addition to scientific articles, PubMed also provides access to advocacy group websites, clinical trial information on ClinicalTrials.gov, and resources like OMIM (Online Mendelian Inheritance in Man) for more in-depth information on 21-hydroxylase deficiency and related disorders.

Scientific articles available on PubMed offer insights into the clinical features of 21-hydroxylase deficiency, ranging from the severe forms that cause life-threatening salt-wasting crises in newborns to the milder non-classic forms that may be undiagnosed until later in life. These articles also provide information on the genetic inheritance of 21-hydroxylase deficiency, as well as the functional consequences of mutations in the 21-hydroxylase gene.

In summary, PubMed is a valuable resource for finding scientific articles and other information about 21-hydroxylase deficiency. It provides a wealth of knowledge on the clinical features, genetic causes, and treatment options for this rare congenital adrenal disorder. Healthcare professionals and individuals affected by 21-hydroxylase deficiency can benefit from the research studies and resources available on PubMed to stay informed and make informed decisions about their health.

References

The following resources have been used for gathering information on 21-hydroxylase deficiency:

• OMIM: Online Mendelian Inheritance in Man – a catalog of human genes and genetic disorders. Available at: https://www.omim.org/
• PubMed: A database of scientific articles and research studies. Available at: https://pubmed.ncbi.nlm.nih.gov/
• ClinicalTrials.gov: A registry of clinical trials and research studies. Available at: https://clinicaltrials.gov/
• 21-Hydroxylase Deficiency Patient Advocacy Group: A patient support group for individuals with 21-hydroxylase deficiency. Additional information can be found at: https://www.21-hydroxylase.org/
• Genetic and Rare Diseases Information Center: Information about rare diseases and genetic disorders. Available at: https://rarediseases.info.nih.gov/
• ClinGen: A resource for clinical genetics information. Available at: https://www.clinicalgenome.org/

These references can provide more information on the clinical characteristics, genetic causes, inheritance patterns, and available testing for 21-hydroxylase deficiency.