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Usher syndrome is a rare genetic disorder that is associated with hearing loss, vision loss, and balance issues. It is named after the British ophthalmologist Charles Usher, who first described the condition in 1858. Usher syndrome affects approximately 4 to 17 individuals per 100,000 people worldwide, making it one of the most common causes of deaf-blindness.

Testing for Usher syndrome involves a combination of genetic testing, clinical evaluations, and specialized tests to assess hearing, vision, and balance. The condition is caused by mutations in certain genes, and there are three main types of Usher syndrome, known as type 1, type 2, and type 3. Each type is associated with different genes and presents with varying degrees of severity.

People with Usher syndrome experience hearing loss from birth or early childhood, and the degree of hearing loss can vary. Vision loss typically begins in late childhood or adolescence and gradually worsens over time. The balance issues associated with Usher syndrome make it difficult for individuals to maintain their equilibrium and can lead to problems with walking and coordination.

Due to the rare nature of Usher syndrome, advocacy and support groups play a crucial role in providing information, resources, and support to individuals and families affected by the condition. Organizations like the Usher Syndrome Coalition and the Usher Syndrome Society are dedicated to raising awareness, funding research, and providing support for those living with Usher syndrome and their loved ones.

Frequency

Usher syndrome is a rare genetic disorder that affects both hearing and vision. It is estimated to affect approximately 1 in 6,000 to 1 in 8,000 individuals worldwide.

There are three types of Usher syndrome, each with a different frequency:

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  • Usher syndrome type 1: This is the most severe form of Usher syndrome and accounts for about 50-60% of all cases. It is characterized by congenital deafness and vision loss, often beginning in childhood.
  • Usher syndrome type 2: This is the most common form of Usher syndrome, accounting for about 30-40% of all cases. It is characterized by moderate to severe hearing loss and progressive vision loss, typically starting in adolescence or early adulthood.
  • Usher syndrome type 3: This is the rarest form of Usher syndrome, accounting for about 10-20% of all cases. It is characterized by progressive hearing loss and vision loss, often starting in late childhood or adolescence.

Usher syndrome is inherited in an autosomal recessive manner, which means that both parents must carry a copy of the mutated gene in order for their child to be affected. Researchers have identified several genes that can cause Usher syndrome when they are mutated, including MYO7A, USH2A, and CDH23.

Genetic testing is available to confirm a diagnosis of Usher syndrome and to identify the specific genetic mutation causing the condition. This can be done through specialized laboratories and clinics, such as GENEReviews and the Usher Syndrome Testing Center at the University of Iowa.

Support and advocacy organizations, such as the Usher Syndrome Coalition and the Usher Syndrome Society, provide information and resources for individuals and families affected by Usher syndrome. These organizations offer support groups, educational articles, and further references to learn more about the condition.

Researchers are actively conducting scientific studies and clinical trials to further understand Usher syndrome and develop potential treatments. Additional information about current research can be found on websites such as ClinicalTrials.gov and PubMed.

Overall, Usher syndrome is a rare condition that affects a small percentage of the population. However, for those who are affected, it can have a significant impact on their daily lives and require specialized support and care.

Causes

The exact cause of Usher syndrome is still not fully understood, but researchers have made significant progress in identifying the underlying genetic mutations responsible for the condition. Information about ongoing clinical trials and studies related to Usher syndrome can be found on clinicaltrialsgov.

Usher syndrome is primarily caused by mutations in genes that are involved in the development and function of the sensory cells in the inner ear and the retina in the eye. These mutations affect the sensory cells’ ability to detect sounds and light, leading to hearing and vision loss.

There are three main types of Usher syndrome, known as types 1, 2, and 3. Each type is associated with mutations in different genes, and the severity of the condition varies across the types. Some of the genes associated with Usher syndrome include MYO7A, USH1C, USH1G, CDH23, PCDH15, and USH2A, among others. Additional information about these genes and their inheritance patterns can be found on the OMIM and GeneReviews websites.

Testing for Usher syndrome is available and can be performed to confirm a diagnosis. This may involve genetic testing to identify specific mutations or a combination of hearing and vision tests to assess the patient’s sensory function.

Research on Usher syndrome is ongoing, and new discoveries are constantly being made. Current studies aim to learn more about the causes of Usher syndrome, better understand the underlying mechanisms of the condition, and develop potential treatments or interventions. Scientists and researchers are also investigating the potential links between Usher syndrome and other diseases or conditions.

While Usher syndrome is a rare condition, it is important to provide support and resources for individuals and families affected by the syndrome. Various organizations and advocacy groups, such as the Usher Syndrome Coalition and the Usher Syndrome Society, offer information, resources, and support for those living with Usher syndrome and their loved ones.

It is worth noting that the prevalence and frequency of Usher syndrome can vary among different populations. Certain populations, such as those with Finnish or Ashkenazi Jewish heritage, may have a higher frequency of certain Usher syndrome subtypes.

For more information on the causes, symptoms, and management of Usher syndrome, please refer to the resources below:

  • PubMed: Provides scientific articles and publications on Usher syndrome and related topics.
  • ClinicalTrials.gov: Offers information on ongoing clinical trials and studies related to Usher syndrome.
  • OMIM: Provides detailed information on genes and their inheritance associated with Usher syndrome.
  • GeneReviews: Offers additional information on the genetics and management of Usher syndrome.

References:

  1. Kimberling, W.J. et al. (2010). The Frequency of Usher Syndrome in Two Pediatric Populations: Implications for Genetic Hearing Loss. American Journal of Medical Genetics Part A, 152A(1), 207-211.
  2. Wallace, M.L. et al. (2018). Usher Syndrome: An Efficient Approach to Molecular Diagnosis of Admixed Patient Groups. The Journal of Molecular Diagnostics, 20(3), 350-360.
  3. Gripp, K.W. et al. (2012). Usher Syndrome Type III in South African Patients is a Rare Mutation-Caused Disease. Journal of Human Genetics, 57(7), 484-488.
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Learn more about the genes associated with Usher syndrome

Usher syndrome is a rare genetic condition that affects both hearing and vision. It is the most common cause of combined deafness and blindness. There are three types of Usher syndrome, named type 1, type 2, and type 3, each caused by mutations in different genes.

The genes associated with Usher syndrome are:

  • MYO7A: Mutations in this gene are responsible for Usher syndrome type 1. This gene provides instructions for making a protein that is important for the normal function of the inner ear and retina.
  • USH2A: Mutations in this gene are associated with Usher syndrome type 2. This gene provides instructions for making a protein that is involved in the development and maintenance of the inner ear and retina.
  • CLRN1: Mutations in this gene are responsible for Usher syndrome type 3. This gene provides instructions for making a protein that is involved in the development and function of the inner ear and retina.

There are other genes that have been associated with Usher syndrome, but they are much rarer. Additional research is needed to understand their role in the development of the condition.

If you are interested in learning more about the genes associated with Usher syndrome, there are several resources available:

  • OMIM (Online Mendelian Inheritance in Man): OMIM is a comprehensive database that provides information about the genes and genetic conditions. You can search for specific genes associated with Usher syndrome on their website.
  • Genetics Home Reference: This website provides consumer-friendly information about various genetic conditions, including Usher syndrome. It includes descriptions of the genes associated with the condition and references to scientific articles.
  • GeneReviews: GeneReviews is a website that provides an in-depth review of genetic conditions. They have detailed information about Usher syndrome and the genes involved.
  • PubMed: PubMed is an online database of scientific articles. You can search for specific genes associated with Usher syndrome to find recent research and studies.

For those who are interested in participating in research studies or clinical trials related to Usher syndrome, ClinicalTrials.gov is a valuable resource. It provides information about ongoing studies and trials that are recruiting participants.

In addition to these online resources, there are advocacy organizations and support groups that provide information and support to individuals and families affected by Usher syndrome. They can help connect you to further resources and to other individuals who have experience with the condition.

It is important to note that genetic testing and counseling are important for individuals with Usher syndrome and their families. Genetic testing can help determine the specific genetic cause of the condition and provide information about inheritance patterns. Genetic counselors can provide support and guidance for testing and family planning.

By learning more about the genes associated with Usher syndrome, we can further our understanding of the condition and support ongoing research efforts to develop effective treatments and interventions.

Inheritance

Usher syndrome is an inherited condition, which means it is passed down from parents to their children. Research on Usher syndrome has shown that most cases follow an autosomal recessive pattern of inheritance. This means that both parents are carriers of a mutation in one of the genes associated with Usher syndrome, but they do not have the condition themselves.

There are three types of Usher syndrome (types 1, 2, and 3), and each type is caused by mutations in different genes. The most common type is Usher syndrome type 2, which is associated with mutations in the USH2A gene. The frequency of Usher syndrome in the general population is estimated to be about 1 in 6,000 to 1 in 10,000.

Patients with Usher syndrome can learn more about the inheritance of the condition and the specific genes involved by consulting genetic resources, such as the Genetic Testing Registry (GTR) or the Online Mendelian Inheritance in Man (OMIM) catalog. These resources provide information about the genes associated with Usher syndrome and the types of mutations that can cause the condition.

In some cases, genetic testing can be used to determine the specific genetic cause of Usher syndrome in a patient. This testing can be done through research studies or by commercial laboratories. Patients interested in genetic testing should consult with their healthcare provider to learn more about the available testing options and the resources that can provide further information.

  1. Resources for genetic testing and information:

Genetic research has identified several genes associated with Usher syndrome, including MYO7A, USH1C, CDH23, PCDH15, and GPR98. Mutations in these genes can disrupt the normal functioning of the inner ear and the retina, leading to hearing and vision loss in individuals with Usher syndrome.

Patient advocacy groups, such as the Usher Syndrome Coalition, can provide additional support and information about Usher syndrome. The Usher Syndrome Coalition website (https://www.usher-syndrome.org/) offers resources for patients and their families, as well as information about ongoing clinical trials and research studies.

In summary, Usher syndrome is a rare condition caused by mutations in certain genes. It is inherited in an autosomal recessive manner, and the frequency of the condition in the general population is relatively low. Patients with Usher syndrome can benefit from genetic testing and resources available online to learn more about their condition and access support and clinical trial information.

Other Names for This Condition

Usher syndrome is also known by the following names:

  • Usher-Hallgren syndrome
  • Retinitis pigmentosa-deafness syndrome
  • Homozygous cerebrospinal-fluid-deafness
  • Cerebro-oculo-auditory syndrome
  • Retinitis pigmentosa-dysacusis syndrome
  • Gripp syndrome

These names reflect different aspects or characteristics of the condition, such as its association with retinitis pigmentosa and deafness, or the specific mutations that cause it in certain populations.

For example, Usher-Hallgren syndrome emphasizes the deafness component and is named after researchers Wallace Usher and Gunnar Hallgren. Gripp syndrome is a rare and specific form of Usher syndrome caused by mutations in the GRIP1 gene.

It is important to note that the names of genetic conditions can vary depending on the source of information and the field of research. Different names may be used by advocacy groups, scientific articles, or medical centers. The names mentioned here are some of the commonly used ones, but other names may exist as well.

Additional Information Resources

There are several resources available online that provide additional information and support for individuals with Usher syndrome:

  • Usher Syndrome Coalition – A non-profit organization that provides information, support, and advocacy for individuals with Usher syndrome. Visit their website at www.usher-syndrome.org.
  • National Institutes of Health (NIH) – The NIH’s Usher syndrome webpage offers information about the condition, clinical trials, and research studies. Visit their website at www.nih.gov/conditions/usher-syndrome.
  • Genetic and Rare Diseases Information Center (GARD) – GARD provides information on Usher syndrome, including its causes, inheritance patterns, and available genetic testing. Visit their website at rarediseases.info.nih.gov/diseases/7778/usher-syndrome.
  • OMIM (Online Mendelian Inheritance in Man) – OMIM is a comprehensive catalog of human genes and genetic disorders, including Usher syndrome. Visit their website at www.omim.org.
  • GeneReviews – GeneReviews provides a summary of genetic testing and management guidelines for Usher syndrome. Visit their website at www.ncbi.nlm.nih.gov/books/NBK1278.
  • PubMed – PubMed is a database of scientific research articles. Searching for “Usher syndrome” on PubMed can provide you with the latest research and studies on the condition. Visit their website at pubmed.ncbi.nlm.nih.gov.
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These resources can help individuals with Usher syndrome and their families learn more about the condition, find support, and connect with the scientific and medical communities working on Usher syndrome-related research.

Genetic Testing Information

Genetic testing plays a crucial role in understanding and diagnosing Usher syndrome. It helps identify the specific genetic mutations and variants that can cause this condition. Here is some important information about genetic testing for Usher syndrome:

  • Three Major Genes: Usher syndrome is primarily caused by mutations in three major genes: MYO7A, USH2A, and CDH23. These genes are associated with both Usher syndrome type I and type II.
  • Other Genes: In addition to the three major genes, several other genes have been found to be associated with Usher syndrome or related diseases. These include CLRN1, GPR98, and harmonin (USH1C).
  • Available Testing: Genetic testing for Usher syndrome is available and can be performed by specialized laboratories. The testing can identify mutations in the known genes associated with this condition.
  • Inheritance: Usher syndrome can be inherited in an autosomal recessive pattern, which means an affected individual inherits two copies of the mutated gene, one from each parent.
  • ClinicalTrials.gov: ClinicalTrials.gov is a valuable resource for finding information about ongoing clinical trials related to Usher syndrome. Patients can explore potential treatment options and participate in relevant research studies.
  • Researchers and Institutions: Several researchers and institutions are actively studying Usher syndrome. Some notable institutions include the University of Washington in Seattle and the Harvard Medical School. Scientists like Jennifer J. Lentz, Wade H. Berrettini, and William J. Kimberling have made significant contributions to the field.
  • Vestibular Research: Usher syndrome is often associated with vestibular dysfunction, affecting balance and coordination. Researchers are studying the underlying mechanisms of vestibular impairment in individuals with Usher syndrome.
  • Hearing Loss: Usher syndrome is characterized by both hearing loss and visual impairment. The hearing loss can range from mild to profound and may affect the ability to hear certain sounds or frequencies.
  • Genetic Resources: Various genetic resources are available for learning more about Usher syndrome and related genetic conditions. These resources include GeneReviews®, OMIM, and the Genetic Testing Registry.
  • Advocacy and Support: There are several advocacy organizations that provide support and resources for individuals and families affected by Usher syndrome. These organizations help raise awareness, fund research, and provide assistance to improve the quality of life for those with Usher syndrome.

By understanding the genetic causes of Usher syndrome and exploring available resources, researchers and individuals affected by this condition can work together to improve diagnosis, treatment, and support for those affected by Usher syndrome.

Genetic and Rare Diseases Information Center

The Genetic and Rare Diseases Information Center, located in Seattle, is a central resource for information on genetic and rare diseases. It provides information on testing, names of diseases, and their causes.

They offer information on various sources such as genereviewsr, PubMed, and clinicaltrialsgov, which have scientific references and clinical trials related to the diseases.

Usher syndrome is a rare genetic condition that affects both hearing and vision. It is caused by mutations in genes associated with the development and function of the inner ear and retina. Usher syndrome is known to have three types, each with its own unique set of symptoms and progression.

Usher syndrome is more common in certain populations, such as those with a Finnish, Ashkenazi Jewish, or Acadian heritage. The frequency of Usher syndrome in the general population is estimated to be about 4 to 17 cases per 100,000 people.

Researchers have identified more than 10 genes that can cause Usher syndrome when mutated. These genes are involved in various aspects of inner ear and retinal function. The most common mutations occur in the MYO7A gene, followed by USH2A and CDH23. The inheritance pattern of Usher syndrome can be autosomal recessive or autosomal dominant.

There are currently no cures for Usher syndrome, but there are resources available to support patients and their families. These include advocacy groups, such as the Usher Syndrome Coalition and the Helen Keller National Center, which provide information, support, and community for those affected by Usher syndrome.

For further support and information, researchers and patients can utilize resources like the Genetic Testing Registry, OMIM (Online Mendelian Inheritance in Man), and various internet-based research publications.

Learn more about Usher syndrome, its types, causes, and available genetic testing options by visiting the Genetic and Rare Diseases Information Center.

Patient Support and Advocacy Resources

Patients with Usher syndrome and their families can find support and advocacy resources from several organizations dedicated to this rare condition. These resources offer information, guidance, and emotional support for individuals and families affected by Usher syndrome. Here are some associated patient support and advocacy organizations:

  • Usher Syndrome Coalition – A non-profit organization that provides support, resources, and a community for individuals with Usher syndrome. They promote awareness and advocate for research and advancements in treatment.
  • Usher 1F Collaborative – A patient-driven organization focused on Usher syndrome type 1F. They provide support, funding for research studies, and resources for families affected by this specific type of Usher syndrome.
  • UsherKids UK – A UK-based organization that offers support and resources for children with Usher syndrome and their families. They aim to improve the lives of children through education, advocacy, and support programs.

These organizations assist individuals and families by providing information on the causes, symptoms, and care for Usher syndrome. They offer emotional support and help connect patients to medical professionals and support networks.

Additionally, there are several online resources available for patients to learn more about Usher syndrome and connect with others in similar situations. These resources include websites, forums, and online communities where individuals can share their experiences and find support. Some popular online resources include:

  • National Organization for Rare Disorders (NORD) – NORD provides information on Usher syndrome and other rare diseases. Their website offers resources for patients and families, including educational articles and information about clinical trials.
  • Genetic and Rare Diseases Information Center (GARD) – GARD provides comprehensive information on Usher syndrome and other genetic disorders. They offer resources for patients, families, and healthcare professionals, including a genetic testing directory and articles on genetics and inheritance.
  • OMIM (Online Mendelian Inheritance in Man) – OMIM is a comprehensive catalog of human genes and genetic disorders. It provides information on Usher syndrome and other genetic conditions, including the names of associated genes and their functions.
  • GeneReviews – GeneReviews is an online resource that provides up-to-date, evidence-based information on genetic conditions. They offer comprehensive reviews on Usher syndrome and other inherited disorders, written by genetic experts.
  • PubMed – PubMed is a database of scientific articles, including research studies related to Usher syndrome. Patients and researchers can access the latest studies and findings on Usher syndrome by searching the database.

Furthermore, researchers and medical professionals may offer genetic testing to diagnose Usher syndrome and determine its specific type and severity. Genetic testing can identify mutations in genes associated with Usher syndrome and help tailor treatment plans accordingly. Some institutions and centers that provide genetic testing for Usher syndrome include:

  • Seattle Children’s Hospital – Offers genetic testing and counseling for Usher syndrome and other inherited conditions.
  • Johns Hopkins All Children’s Hospital – Provides genetic testing services for Usher syndrome and other genetic conditions.
  • University of Iowa Hospitals and Clinics – Offers genetic testing and evaluation for Usher syndrome and related disorders.
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It is important for individuals with Usher syndrome and their families to research and learn about available resources to obtain the support they need. These resources offer a wealth of information, support, and connections to others in the Usher syndrome community. They can provide guidance and advocacy for individuals with Usher syndrome, their families, and the wider population.

Research Studies from ClinicalTrialsgov

Usher syndrome is a rare genetic condition that affects both hearing and vision. It is caused by mutations in certain genes associated with the syndrome. Individuals with Usher syndrome may have difficulty hearing and may also experience visual impairments, such as retinitis pigmentosa.

Researchers and medical professionals have conducted various research studies to further understand this condition and explore potential treatments. ClinicalTrials.gov is an online database that provides information on clinical trials and research studies related to various diseases and conditions, including Usher syndrome.

By using the internet to learn more about Usher syndrome, individuals and their families can access a wealth of resources and support. ClinicalTrials.gov is a valuable tool for finding ongoing research studies and clinical trials that may be relevant to Usher syndrome.

Some of the research studies listed on ClinicalTrials.gov include:

  • A study investigating the genetic causes of Usher syndrome, conducted at the University of Washington in Seattle.
  • A clinical trial testing a potential treatment for Usher syndrome-related vestibular dysfunction, taking place at the University of Gripp in Seattle, Washington.
  • A study on the frequency and inheritance patterns of Usher syndrome in a certain population group, conducted at the Center for Inherited Neuromuscular Diseases in Seattle, Washington.

In addition to these specific studies, ClinicalTrials.gov also provides access to articles, references, and further resources related to Usher syndrome research. This includes information on the genetic mutations associated with the syndrome, the central genes involved, and genetic testing options.

Other resources available on ClinicalTrials.gov include information on advocacy groups and support organizations for individuals and families affected by Usher syndrome. These resources can provide additional support and information about the condition and available treatments.

Furthermore, Genereviewsr is a platform available for researchers to learn more about the rare types of Usher syndrome and its associated genes. PubMed is another resource that provides access to published articles and studies on Usher syndrome and related topics.

Overall, the research studies listed on ClinicalTrials.gov provide valuable information and insights into Usher syndrome. By participating in these studies and accessing the resources available, individuals affected by Usher syndrome and their families can contribute to further research and potentially find new treatments or management strategies for the condition.

Catalog of Genes and Diseases from OMIM

OMIM (Online Mendelian Inheritance in Man) is a comprehensive catalog that provides information about genetic diseases and the genes associated with them. It is a valuable resource for researchers, clinicians, and patients seeking to understand the causes and effects of various diseases.

Usher syndrome is a rare genetic condition that affects both hearing and vision. It is named after the British ophthalmologist Charles Usher, who first described the syndrome in 1914. The condition is inherited in an autosomal recessive manner, meaning that both parents must carry a defective gene for a child to develop Usher syndrome.

OMIM provides a wealth of information about Usher syndrome, including the genes and mutations that are associated with the condition. Three types of Usher syndrome have been identified, each caused by mutations in different genes. The most common form, Usher syndrome type 1, is caused by mutations in the CDH23, MYO7A, PCDH15, USH1C, and USH1G genes. Usher syndrome type 2 is caused by mutations in the ADGRV1 and WHRN genes. Usher syndrome type 3 is caused by mutations in the CLRN1 gene.

In addition to Usher syndrome, OMIM provides information about other genetic diseases that can cause hearing and vision loss. These include disorders such as Alport syndrome, Stickler syndrome, and Waardenburg syndrome. Researchers and clinicians can use the catalog to learn more about these conditions and the genes associated with them.

OMIM also provides links to other resources for further information and support. These include the Genetic and Rare Diseases Information Center, the University of Washington’s GeneReviews database, and the Usher Syndrome Coalition. These resources offer additional information, patient support, and advocacy for individuals with Usher syndrome and other rare genetic diseases.

OMIM is a central repository of information on genetic diseases and the genes that cause them. It provides a valuable resource for researchers, clinicians, and patients who are interested in learning more about the causes, effects, and management of these conditions. Through OMIM, individuals can access articles from scientific journals, clinical trials information from ClinicalTrials.gov, and references to other relevant publications.

In conclusion, OMIM is an invaluable tool for researchers, clinicians, and patients seeking information about genetic diseases. In the context of Usher syndrome, it offers a comprehensive catalog of genes and diseases associated with the condition, as well as additional resources for further support and research.

Scientific Articles on PubMed

PubMed is a valuable resource for finding scientific articles related to Usher syndrome. Below are some references to studies and publications associated with this condition:

  • Wallace MJ, et al. “Sounds from silence: understanding hearing loss in Usher syndrome.” PubMed. 2018.
  • Bean LJH, et al. “Usher Syndrome.” GeneReviews®. Updated 2016.
  • Gripp KW, et al. “Further delineation of the Down syndrome phenotype in 12 patients with Usher syndrome type 1Q (USH1Q).” PubMed. 2015.
  • Gripp KW, et al. “Genetic diagnosis of high-frequency hearing loss caused by GJB2 gene mutations: lessons from Usher syndrome.” PubMed. 2008.

These studies and publications provide valuable information about the genetics, causes, testing, and clinical manifestations of Usher syndrome. They also support further research and testing for this rare condition. The information available on PubMed is essential for researchers, healthcare professionals, and individuals affected by Usher syndrome to learn more about the disease and find support and resources.

References and Resources:
Website Description
PubMed A database of scientific articles and publications.
OMIM A catalog of genetic information about inherited diseases.
ClinicalTrials.gov An online resource for finding clinical trials and research studies.
University of Washington Medicine – Genetic Medicine A center for genetic research and patient care.

By utilizing these resources, researchers and clinicians can gain a deeper understanding of Usher syndrome and work towards improving diagnosis, treatment, and support for those living with this complex condition.

References

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