Vitamin D-dependent rickets, also called VDDR, is a rare genetic condition that affects the normal growth and development of bones. It is caused by mutations in certain genes that help control the body’s ability to absorb and use vitamin D. There are two types of VDDR: type I and type II.

In type I VDDR, the genetic mutations affect a gene called CYP27B1, which is responsible for the production of an enzyme that converts inactive vitamin D into its active form, called calcitriol. Without calcitriol, the body cannot properly absorb calcium from the diet, leading to weak and brittle bones.

In type II VDDR, the genetic mutations affect a gene called VDR, which encodes a protein called the vitamin D receptor. The vitamin D receptor is responsible for binding to calcitriol and helping it carry out its functions in the body. Mutations in the VDR gene result in a reduced ability of calcitriol to regulate calcium and phosphorus levels, leading to weakened bones.

VDDR can also be associated with other genetic conditions, such as alopecia, a condition that causes hair loss. The condition can be inherited in an autosomal recessive manner, meaning that both parents must carry the mutated gene for their child to be affected.

The frequency of VDDR is not well known, but it is considered a rare disease. Diagnosis is typically made based on the clinical presentation of symptoms, such as weak and bowed legs, delayed growth, and dental problems. Testing for VDDR may involve measuring vitamin D and calcium levels in the blood, as well as genetic testing to identify the specific mutations.

Although there is no cure for VDDR, treatment typically involves high-dose vitamin D supplementation and calcium to help strengthen the bones. In some cases, calcitriol or other vitamin D analogs may be used to replace the missing calcitriol function.

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Patient advocacy organizations and resources, such as the Vitamin D-dependent Rickets Patient Advocacy Group and the Online Mendelian Inheritance in Man (OMIM) catalog, provide additional information and support for individuals with VDDR and their families. Scientific articles and references on VDDR can also be found on PubMed, a database of medical literature.

Frequency

Vitamin D-dependent rickets, type 2B (VDDR2B) is a rare genetic condition with autosomal recessive inheritance. It is caused by mutations in the vitamin D receptor gene (VDR). VDDR2B affects the calcitriol-vitamin D receptor (VDR) complex, which plays a crucial role in the processes that control bone growth and mineralization. Mutations in the VDR gene result in a deficiency in the VDR protein, which leads to impaired responses to calcitriol (the active form of vitamin D) and subsequent rickets.

The frequency and causes of VDDR2B are not well-established due to the rarity of this condition. However, it is estimated to occur in approximately 1 in 100,000 to 1 in 200,000 births.

VDDR2B can present with a variety of symptoms, including bone deformities, growth retardation, alopecia (hair loss), and more. The severity of the condition can vary, and it can also be associated with other forms of VDD Rickets, such as VDDR1A.

Diagnosis of VDDR2B can be confirmed through genetic testing, which identifies mutations in the VDR gene. Genetic testing can also help differentiate VDDR2B from other types of genetic rickets. In addition, laboratory tests, such as measuring serum calcium, phosphorus, and alkaline phosphatase levels, can provide supportive information for the diagnosis.

Management of VDDR2B involves addressing the underlying vitamin D deficiency and providing appropriate treatment. This typically includes vitamin D supplementation and a diet rich in calcium and phosphorus. Regular monitoring and follow-up is essential to ensure optimal bone health and growth in affected individuals.

For more information about VDDR2B and related genetic diseases, the following resources may be helpful:

• OMIM (Online Mendelian Inheritance in Man): VDDR2B
• PubMed Central (PMC): VDDR2B
• GeneReviews: Vitamin D-Dependent Rickets Type 2B
• Genetic and Rare Diseases Information Center (GARD): Vitamin D-Dependent Rickets Type 2B
• ClinVar: VDR gene

Although VDDR2B is a rare condition, understanding its frequency, causes, and associated genes can help in diagnosing and managing patients with this condition. Further research and scientific articles are needed to learn more about VDDR2B and its genetic processes.

Causes

Vitamin D-dependent rickets (VDDR) is a rare genetic condition that affects bone growth. It is also known as hereditary vitamin D-resistant rickets, vitamin D-dependent rickets type 2A (VDDR2A), or autosomal recessive vitamin D-dependent rickets.

This condition is caused by mutations in the VDR gene, which provides instructions for making the vitamin D receptor protein. The vitamin D receptor forms a complex with calcitriol, a form of vitamin D, and helps control the expression of genes involved in bone growth and other important processes.

Individuals with VDDR have mutations in the VDR gene that prevent the vitamin D receptor from functioning properly. As a result, they are unable to carry out normal processes, such as the absorption of calcium and phosphate from the intestines, which are necessary for bone development.

There are different types of VDDR, each associated with different genes. The most common form is VDDR type 1A (VDDR1A), which is caused by mutations in the CYP27B1 gene. This gene provides instructions for making an enzyme called 1-alpha-hydroxylase, which converts inactive forms of vitamin D into active forms that can be used by the body.

In VDDR1A, mutations in the CYP27B1 gene result in a deficiency of active vitamin D, leading to impaired calcium and phosphate absorption and subsequent bone abnormalities.

Another form of VDDR, called VDDR type 1B (VDDR1B), is caused by mutations in the CYP2R1 gene. This gene provides instructions for making an enzyme called 25-hydroxylase, which converts vitamin D into a form that can be activated by the liver and kidneys.

Individuals with VDDR1B have mutations in the CYP2R1 gene that impair the production of active vitamin D, leading to similar symptoms as VDDR1A.

Other rare forms of VDDR include VDDR type 2B (VDDR2B), caused by mutations in the VDRL gene, and VDDR type 3 (VDDR3), caused by mutations in the CYP11A1 gene. These forms of VDDR have similar symptoms to VDDR1A and VDDR1B, but the underlying genetic mutations are different.

VDDR can also be caused by certain inherited conditions that affect the metabolism of vitamin D or the function of the vitamin D receptor. For example, VDDR can occur in individuals with alopecia universalis, a condition characterized by complete hair loss.

It is important to note that not all cases of VDDR are genetic. Some individuals may have vitamin D deficiency or impaired vitamin D metabolism due to other factors, such as inadequate vitamin D intake, lack of sunlight exposure, or certain medical conditions.

For more scientific information about the causes of vitamin D-dependent rickets, you can refer to resources such as the OMIM (Online Mendelian Inheritance in Man) catalog, PubMed articles, and clinical genetics websites.

Learn more about the genes associated with Vitamin D-dependent rickets

Vitamin D-dependent rickets (VDDR) is a genetic condition caused by mutations in certain genes. These genes control the production and function of vitamin D, a hormone that helps your body absorb calcium and phosphorus from the food you eat.

There are three types of VDDR, known as VDDR type 1A, VDDR type 1B, and VDDR type 2.

VDDR type 1A:

• This type of VDDR is caused by mutations in the CYP27B1 gene. This gene provides instructions for making an enzyme called calcitriol 1-hydroxylase, which helps convert vitamin D into its active form.
• People with VDDR type 1A have a deficiency of this enzyme, which leads to low levels of active vitamin D and subsequently affects calcium and phosphorus absorption.

VDDR type 1B:

• VDDR type 1B is caused by mutations in the CYP2R1 gene. This gene provides instructions for making an enzyme called 25-hydroxylase, which helps convert vitamin D into its active form.
• The mutations in the CYP2R1 gene reduce the activity of the enzyme, resulting in lower levels of active vitamin D and impaired calcium and phosphorus absorption.

VDDR type 2:

• VDDR type 2 is caused by mutations in the VDR gene. This gene provides instructions for making the vitamin D receptor, which helps regulate the genes involved in calcium absorption and bone health.
• These mutations impair the function of the vitamin D receptor, leading to reduced calcium absorption and weakened bones.

VDDR type 1A and VDDR type 1B are inherited in an autosomal recessive manner, which means both copies of the gene must be mutated to develop the condition. VDDR type 2, on the other hand, can be inherited in an autosomal dominant or autosomal recessive manner.

To learn more about the specific genes associated with VDDR, you can refer to the Online Mendelian Inheritance in Man (OMIM) catalog. OMIM provides detailed information about the genes, the mutations that cause VDDR, and additional resources for further reading.

Genes	OMIM ID
CYP27B1	609506
CYP2R1	608713
VDR	601769

Although VDDR is a rare condition, understanding the genetic basis of the disease can provide valuable insights into the underlying biological processes. This knowledge can help in the development of targeted therapies, genetic testing, and support for individuals and families affected by VDDR.

For more information on VDDR and other genetic diseases, you can also refer to scientific articles, advocacy organizations, and genetic counseling resources.

Inheritance

Vitamin D-dependent rickets (VDDR) is an inherited disorder characterized by a failure of the body to properly use vitamin D to control calcium and phosphate levels in the bones. There are two types of VDDR: type 1 and type 2.

Type 1 VDDR, also known as autosomal recessive vitamin D-dependent rickets (AR VDDR), is caused by mutations in the VDR gene. This gene provides instructions for making a protein called the vitamin D receptor (VDR), which is responsible for responding to calcitriol, the active form of vitamin D, in the body. In AR VDDR, the mutations in the VDR gene result in a defective VDR protein, making the body unable to respond to calcitriol properly.

Type 2 VDDR, also called autosomal recessive alopecia and hypogonadism (ARAHP), is caused by mutations in the VDDRB gene. This gene provides instructions for making a protein called the vitamin D receptor 2B (VDDR2B), which also plays a role in responding to calcitriol. Mutations in the VDDRB gene result in a defective VDDR2B protein, leading to the onset of VDDR symptoms.

The inheritance pattern for both types of VDDR is autosomal recessive, which means that the condition is caused by inheriting two copies of the mutated gene, one from each parent. Individuals with only one copy of the mutated gene are carriers and do not show symptoms of VDDR.

Genetic testing can be used to diagnose VDDR and determine the specific gene mutation involved. This information helps in providing accurate genetic counseling and support for affected individuals and their families. Additionally, it aids in the identification of carriers in the family and supports control of the condition through proper management and treatment.

There are several published articles and resources available that provide more information about the genetic causes, inheritance patterns, and processes involved in VDDR. These resources can be found in scientific journals, as well as on websites and databases such as PubMed, OMIM, and clinVar. They offer valuable information for healthcare professionals, researchers, and individuals affected by VDDR.

In summary, VDDR is an inherited condition with two types: type 1 and type 2. Type 1 VDDR is caused by mutations in the VDR gene, while type 2 VDDR is caused by mutations in the VDDRB gene. Both types of VDDR have autosomal recessive inheritance, and genetic testing can help in diagnosis and management of the condition.

Other Names for this Condition

Vitamin D-dependent rickets, also known as D-dependent rickets or VDDR, is a rare genetic condition that affects the bones. It is caused by mutations in the VDDR1A and VDDR1B genes that are involved in the production and function of the vitamin D receptor (VDR).

There are two main types of vitamin D-dependent rickets:

• VDDR1A: This type is caused by mutations in the VDDR1A gene. It is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition. Patients with VDDR1A have normal or slightly elevated levels of 1,25-dihydroxyvitamin D, but their bodies cannot respond to it properly.
• VDDR1B: This type is caused by mutations in the VDDR1B gene. It is also inherited in an autosomal recessive manner. Patients with VDDR1B have low or undetectable levels of 1,25-dihydroxyvitamin D, which is the active form of vitamin D that helps to regulate calcium and phosphate levels in the body.

Other names for vitamin D-dependent rickets include:

• VDD1
• Vitamin D-dependent rickets, types 1A and 1B
• Vitamin D receptor deficiency type 1A and 1B
• Calcitriol-VDR resistance
• VDRD1A and VDRD1B

Vitamin D-dependent rickets can cause a range of symptoms, including weak and brittle bones, leg deformities, dental problems, alopecia (hair loss), and muscle weakness. The severity of symptoms can vary depending on the specific type and genetic mutations involved.

There is currently no cure for vitamin D-dependent rickets, but treatment focuses on managing symptoms and preventing complications. This may involve vitamin D and calcium supplements, medications to help improve bone mineralization, and physical therapy to improve muscle strength and mobility.

Support and advocacy groups, such as the Vitamin D Council and the National Organization for Rare Disorders (NORD), provide additional information, resources, and support for patients and their families affected by vitamin D-dependent rickets. These organizations also play a role in raising awareness about the condition and advocating for further research and genetic testing.

For more information about vitamin D-dependent rickets, genetics, and related conditions, you can visit the websites of the National Institutes of Health’s Office of Rare Diseases Research (ORDR) and the Online Mendelian Inheritance in Man (OMIM) catalog. Scientific articles and references on PubMed can also provide valuable information on the topic.

Additional Information Resources

Here are some additional resources to learn more about Vitamin D-dependent rickets:

• Calcitriol-VDR: A gene that encodes a protein called vitamin D receptor (VDR). Mutations in this gene can cause vitamin D-dependent rickets. Visit the Gene Review for more information.
• Vitamin D-resistant rickets: Also known as autosomal recessive vitamin D-resistant rickets. This rare condition is caused by mutations in genes that are involved in the body’s ability to respond to vitamin D. OMIM provides more information about this genetic disorder.
• Calcitriol: The active form of vitamin D that helps in the absorption of calcium and phosphorus and promotes normal bone growth. Learn more about calcitriol on PubMed.
• Other genes: Although VDR and calcitriol-vdr are important genes associated with vitamin D-dependent rickets, there are other genes that play a role in the condition. Explore PubMed for scientific articles on this topic.
• Causes: Vitamin D-dependent rickets can be caused by mutations in genes involved in the production or processing of calcitriol. These mutations result in a decreased ability to absorb calcium and phosphorus, leading to weak bones and other complications. Visit Genetics Home Reference to learn more about the genetic causes of vitamin D-dependent rickets.
• Inheritance: Vitamin D-dependent rickets is typically inherited in an autosomal recessive pattern, which means that both parents must carry a copy of the mutated gene in order for the condition to occur. Find more information about the inheritance patterns on Genetics Home Reference.
• Patient support: For additional support and advocacy for patients with vitamin D-dependent rickets and their families, visit organizations like Vitamin D-Dependent Rickets Advocacy.
• Scientific information: For more scientific information on the condition, its forms, causes, and treatment options, refer to scientific articles and studies available on PubMed.

Genetic Testing Information

In the context of Vitamin D-dependent rickets, genetic testing can provide valuable information about the underlying causes of the condition. This testing can help identify specific gene mutations that are responsible for the development of the disease.

Vitamin D-dependent rickets is caused by mutations in genes that are involved in the normal processes of vitamin D metabolism and absorption. There are several forms of this condition, including Vitamin D-dependent rickets type 1A (VDDR1A) and Vitamin D-dependent rickets type 1B (VDDR1B).

VDDR1A is an autosomal recessive disorder, meaning that both copies of the gene responsible for the condition must be mutated in order for an individual to have the disease. On the other hand, VDDR1B is inherited in an autosomal dominant manner, meaning that a mutation in just one copy of the gene is sufficient to cause the disease.

Genetic testing can help identify these mutations, which can be helpful for a patient in understanding their condition and informing their treatment plan. Additionally, genetic testing can help determine the inheritance pattern of the disease and provide information for genetic counseling.

In addition to VDDR1A and VDDR1B, there are also other genes associated with Vitamin D-dependent rickets, including the calcitriol-vdr receptor gene and the alopecia gene.

Genetic testing can be done through various methods, including sequencing of specific genes or analyzing specific regions of the genome. It is important to note that genetic testing may not be available for all forms of Vitamin D-dependent rickets and is typically done in specialized genetic testing laboratories.

Patients and healthcare providers can find more information on genetic testing for Vitamin D-dependent rickets through various resources, including online databases such as OMIM (Online Mendelian Inheritance in Man) and PubMed. These resources provide access to articles, catalog information on specific genes and their associated diseases, and provide references for further reading.

Support and advocacy groups for patients with Vitamin D-dependent rickets can also provide additional information about genetic testing and connect individuals with resources for testing and support.

Patient Support and Advocacy Resources

Patients with Vitamin D-dependent rickets (VDDR) require comprehensive support and advocacy resources to help manage their condition. The following resources can provide patients and their families with valuable information, support, and assistance.

1. Vitamin D-dependent Rickets GeneReview – This comprehensive review, available on PubMed, provides detailed information about VDDR, including the different types, inheritance patterns, and genetic testing.
2. Alopecia Areata Foundation – While VDDR is primarily associated with bone growth and mineralization, some patients may also experience hair loss or alopecia. The Alopecia Areata Foundation offers resources and support for individuals with this condition.
3. OMIM Catalog of Human Genes and Genetic Disorders – The Online Mendelian Inheritance in Man (OMIM) catalog provides a wealth of scientific information about genetic diseases, including VDDR. Patients and their families can learn more about the genes involved, inheritance patterns, and additional associated conditions.
4. Calcitriol-VDR Rickets, Type 2B – This specific type of VDDR, also known as VDDR2B, is caused by mutations in the VDR gene. Patients can find resources specific to this rare condition and connect with others who have been diagnosed with VDDR2B.
5. Genetic and Rare Diseases Information Center – This resource from the National Institutes of Health provides information about a wide range of genetic and rare diseases, including VDDR. Patients can learn more about the condition, find support groups, and access clinical trials or other research opportunities.

It’s important for patients with VDDR and their families to have access to reliable support and advocacy resources. These resources can help patients better understand their condition, learn about available treatment options, and connect with others who share similar experiences.

Catalog of Genes and Diseases from OMIM

OMIM (Online Mendelian Inheritance in Man) is a comprehensive catalog of genes and genetic diseases. It provides valuable information for patients, clinicians, and researchers about various genetic conditions, including Vitamin D-dependent rickets (VDDR).

Vitamin D-dependent rickets is a genetic disorder that affects bone growth and development. It is caused by mutations in certain genes, such as VDR and CYP27B1. VDDR can be classified into two types: VDDR type 1A (VDDR1A) and VDDR type 2B (VDDR2B).

VDDR1A is caused by mutations in the CYP27B1 gene, which is involved in the production of an active form of vitamin D called calcitriol. Without calcitriol, the body cannot properly absorb calcium and phosphate, leading to weak and soft bones.

VDDR2B, also known as hereditary vitamin D-resistant rickets (HVDRR), is caused by mutations in the VDR gene. This gene encodes the vitamin D receptor, which is responsible for transmitting the effects of vitamin D in the body. Mutations in the VDR gene prevent the receptor from functioning properly, resulting in impaired bone growth and calcitriol resistance.

In addition to VDDR, OMIM provides information about other genetic diseases and conditions. These include alopecia, certain types of inherited bone disorders, and various forms of genetic rickets.

OMIM is a valuable resource for learning more about genetic diseases and their genetic inheritance patterns. It provides information on the frequency of certain genetic conditions, their clinical features, genetic testing options, and available resources and support for patients and families.

OMIM articles often include information about the underlying genetic processes involved in a particular condition, helping researchers better understand the causes and mechanisms of genetic diseases.

Although OMIM is a reliable source of information, it is important to consult additional resources and consult with healthcare professionals for accurate diagnosis and treatment. PubMed, a database of scientific publications, is one such resource that provides more scientific information on genetic diseases, including VDDR.

Summary of Vitamin D-dependent rickets types and associated genes

Type of VDDR	Associated Genes
VDDR1A	CYP27B1
VDDR2B (HVDRR)	VDR

Genetic testing can help diagnose VDDR and determine the specific gene mutations causing the condition. This information is crucial for understanding the inheritance pattern of the disease, providing appropriate treatment, and offering genetic counseling to affected individuals and their families.

OMIM’s catalog of genes and diseases, including VDDR and other genetic conditions, serves as a valuable resource for patients, clinicians, and researchers in the field of genetics.

Scientific Articles on PubMed

Vitamin D-dependent rickets is a rare inherited disorder that affects the normal development of bones. There are two types of vitamin D-dependent rickets, called type 1 and type 2. These types are caused by mutations in different genes and have different patterns of inheritance.

Type 1 vitamin D-dependent rickets is caused by mutations in the CYP27B1 gene, which is involved in the production of calcitriol, the active form of vitamin D. This type is inherited in an autosomal recessive pattern, meaning that both parents must carry a mutated gene for their child to develop the disorder.

Type 2 vitamin D-dependent rickets is caused by mutations in the VDR gene, which affects the function of the vitamin D receptor. This type is also inherited in an autosomal recessive pattern.

Both types of vitamin D-dependent rickets result in weak and poorly developed bones, leading to symptoms such as bone pain, delayed growth, and skeletal abnormalities. Other associated features may include alopecia (hair loss) and secondary hyperparathyroidism.

Although vitamin D-dependent rickets is rare, there have been several scientific articles published on the topic. PubMed, a database of scientific articles, is a valuable resource for finding information and references on this subject.

Research articles on PubMed provide important information about the genetic causes of vitamin D-dependent rickets, diagnostic tools such as genetic testing, and potential treatment options. These articles also support advocacy and patient support groups by providing information and resources for affected individuals and their families.

The frequency of genetic mutations associated with vitamin D-dependent rickets varies among different populations. This information can be useful for genetic counseling and screening.

Some names associated with vitamin D-dependent rickets include VDDR1A (caused by mutations in the gene CYP27B1), VDDR1B (caused by mutations in the gene CYP2R1), and VDDR2A (caused by mutations in the gene VDR).

The OMIM catalog provides detailed information about the genes and genetic variants associated with vitamin D-dependent rickets, including inheritance patterns, clinical features, and references to scientific publications.

In conclusion, scientific articles on PubMed provide valuable information about the types, causes, and genetic basis of vitamin D-dependent rickets. This information helps healthcare professionals, researchers, and patients understand and control this rare disorder.

References

1. Vitamin D-dependent rickets type 1B
2. ‘
   Vitamin D-dependent rickets, type 2A
3. Vitamin D-dependent rickets, type 2B
4. Vitamin D-dependent rickets, type 2C
5. Vitamin D-dependent rickets, type 2D
6. Vitamin D-dependent rickets, type 2E
7. Calcitriol-resistant rickets with alopecia
8. Genetic analyses in vitamin D-dependent rickets type 2A

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

• Clinical Genetics
• Genetics Home Reference
• PubMed
• Online Mendelian Inheritance in Man (OMIM)

Additional articles, scientific papers, and advocacy support for patients with vitamin D-dependent rickets can be found in the catalog of PubMed.