Question 1

What is Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Tatton-Brown-Rahman overgrowth syndrome is a rare disorder characterized by overgrowth, distinctive facial features, and mild to moderate intellectual disability. Caused by changes in the DNMT3A gene, this condition affects multiple systems including the central nervous system and skeletal development. It is inherited in an autosomal dominant pattern and is recognized for its characteristic facial dysmorphism and neurodevelopmental challenges. In plain terms, it affects fewer than 1 in 1,000,000 people.

Question 2

What are the symptoms of Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Individuals with Tatton-Brown-Rahman overgrowth syndrome typically present with a constellation of features. The characteristic findings include a round face, heavy horizontal eyebrows, and narrow palpebral fissures along with an exaggerated cupid's bow, everted upper lip vermilion, deep philtrum, and anteverted nares. Additional consistent features are overgrowth, intellectual disability, global developmental delay, and hypotonia; many also experience congenital heart defects such as ventricular septal defect and other anomalies including Chiari type I malformation and talipes valgus. Not all individuals experience all features, and severity varies considerably, with some developing scoliosis, macrocephaly, or even febrile seizures during early childhood.

Question 3

What causes Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Tatton-Brown-Rahman overgrowth syndrome is caused by pathogenic variants in the DNMT3A gene, a gene important for regulating DNA methylation and normal development. The condition follows an autosomal dominant inheritance pattern, meaning that a single copy of the altered gene can result in the disorder. As with many autosomal dominant conditions, there can be variable expressivity, with affected individuals showing a range of symptom severity. Families are encouraged to seek genetic counseling to discuss inheritance implications and options for family planning. Associated genes include DNMT3A.

Question 4

How is Tatton-Brown-Rahman overgrowth syndrome inherited?

Accepted Answer

Tatton-Brown-Rahman overgrowth syndrome follows an autosomal dominant inheritance pattern. This means inheriting just one copy of the altered gene from either parent can cause the condition.

Question 5

How rare is Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Tatton-Brown-Rahman overgrowth syndrome is classified as very rare. The estimated prevalence is approximately <1 in 1,000,000. Because rare disease data can be limited, actual numbers may differ from published estimates.

Question 6

How is Tatton-Brown-Rahman overgrowth syndrome diagnosed?

Accepted Answer

Definitive diagnosis of Tatton-Brown-Rahman overgrowth syndrome is achieved through molecular genetic testing that identifies pathogenic variants in the DNMT3A gene. Clinical evaluation, including a review of developmental history, characteristic physical features, and a family history of overgrowth or intellectual disability, is also central to the diagnostic process. Because many of these features can overlap with other conditions, genetic testing is essential to confirm the diagnosis and distinguish it from similar disorders.

Question 7

Are there treatments for Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Currently, management focuses on supportive care and symptom management, as no treatments are specifically approved for Tatton-Brown-Rahman overgrowth syndrome. Treatment is tailored to the individual and typically involves a multidisciplinary team to address the various aspects of the condition. Regular surveillance is an essential part of long-term care, helping to identify potential complications—in particular, monitoring developmental progress, cardiac function, and musculoskeletal issues. Patients and families are encouraged to discuss treatment options with their healthcare team and consider genetic counseling for further guidance.

Question 8

Where can I find support for Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Patient advocacy organizations for Tatton-Brown-Rahman overgrowth syndrome include Tatton Brown Rahman Syndrome Community. These organizations can provide information, connect you with other families, and help navigate care. Visit the Support section of this page for full details and contact information.

Question 9

What complications should we watch for in someone with Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Individuals with Tatton-Brown-Rahman overgrowth syndrome may face various complications, including congenital heart defects like ventricular septal defect and other anomalies such as Chiari type I malformation. It's also important to monitor for developmental issues, scoliosis, macrocephaly, and hypotonia. Regular check-ups with healthcare providers can help identify and manage these complications early.

Question 10

How does Tatton-Brown-Rahman overgrowth syndrome affect daily life for individuals?

Accepted Answer

Daily life for individuals with Tatton-Brown-Rahman overgrowth syndrome can vary greatly depending on the severity of their symptoms. Many may experience challenges with intellectual disability and global developmental delay, which can affect learning and social interactions. Supportive care and tailored educational plans can help improve their quality of life and assist them in reaching their potential.

Question 11

What is the prognosis for someone diagnosed with Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

The prognosis for individuals with Tatton-Brown-Rahman overgrowth syndrome varies widely based on symptom severity and access to specialized care. Many individuals can achieve a good quality of life, although they may encounter challenges related to intellectual disability and other health issues. With ongoing support and appropriate interventions, some may have a stable developmental trajectory.

Question 12

Are there specific specialists recommended for managing Tatton-Brown-Rahman overgrowth syndrome?

Accepted Answer

Managing Tatton-Brown-Rahman overgrowth syndrome often requires a multidisciplinary team of specialists. Families are encouraged to connect with geneticists, developmental pediatricians, cardiologists, and other healthcare providers who understand the condition. This collaborative approach helps address the various aspects of the syndrome and ensures comprehensive care for the individual.

Organ System	Phenotype Count	Example Features
Brain and nerves	5	Seizure, Enlarged brain ventricles (ventriculomegaly), Intellectual disability
Head and neck	4	Everted upper lip vermilion, Sagittal craniosynostosis, Round face
Heart and blood vessels	3	Ventricular septal defect, Mitral regurgitation, Atrial septal defect
Muscles	1	Low muscle tone (hypotonia)
Pregnancy and birth	1	Fetal distress
Growth and development	1	Tall stature
Bones and joints	1	Sideways curvature of the spine (scoliosis)
Eyes	1	Optic nerve hypoplasia

Feature	% of Persons w/Feature	Comment
Intellectual disability	100%	Most often in mild-to-moderate range
Overgrowth1	80%

Gene(s)	Disorder	MOI	Clinical Characteristics
BRWD3	BRWD3-related OGID (OMIM 300659)	XL	Macrocephaly; Obesity; Mild-to-moderate ID; Tall chin, prognathism, broad forehead, prominent supraorbital ridge
CHD8	CHD8-related OGID (See CHD8-Related Neurodevelopmental Disorder with Overgrowth.)

System/Concern	Evaluation	Comment
Constitutional	Measurement of weight, length/height, head circumference	To assess for macrosomia
Development	Developmental assessment	To incl motor, adaptive, cognitive, speech-language eval; Eval for early intervention/ special education Neurobehavioral/
Psychiatric	Neuropsychiatric eval	For persons age 12 mos: screening for concerns incl sleep disturbances, ADHD, anxiety, /or findings suggestive of ASD
Neurologic	Neurologic eval	Consider brain MRI if indicated by clinical symptoms.; Consider EEG if seizures are a concern.
Musculoskeletal	Orthopedics / physical medicine rehab/ PT OT eval

Research Type	Count	% of Total
Patient case studies	26	50%
Disease patterns and progression	10	19%
Research summaries	6	12%
Other research	4	8%
Laboratory research	4	8%
Testing and diagnosis research	1	2%
New treatment approaches	1	2%

Kisho

Tatton-Brown-Rahman overgrowth syndrome

Overview

Clinical Presentation

Clinical Guidance

Explore clinical features

Genetic Landscape

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Differential Diagnosis

Treatment

Management Guidelines

Therapies Under Investigation

Clinical Trials

Prognosis

Surveillance Guidelines

Constitutional

Development

Psychiatric

Neurologic

Musculoskeletal

Respiratory

Lymphatic

Community

Cardiovascular

Research Landscape

Recent Publications

Patient Support

Patient Advocacy Groups

Medical References

External Resources

OMIM

Orphanet

GARD

Questions for Your Care Team

Questions for Your Care Team

FAQ

Frequently Asked Questions

Tatton-Brown-Rahman overgrowth syndrome

Overview

Clinical Presentation

Clinical Guidance

Explore clinical features

Genetic Landscape

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Differential Diagnosis

Treatment

Management Guidelines

Therapies Under Investigation

Clinical Trials

Prognosis

Surveillance Guidelines

Constitutional

Development

Psychiatric

Neurologic

Musculoskeletal

Respiratory

Lymphatic

Community

Cardiovascular

Research Landscape

Recent Publications

Patient Support

Patient Advocacy Groups

Medical References

External Resources

OMIM

Orphanet

GARD

Related Diseases

Questions for Your Care Team

Questions for Your Care Team

FAQ

Frequently Asked Questions

What is Tatton-Brown-Rahman overgrowth syndrome?

What are the symptoms of Tatton-Brown-Rahman overgrowth syndrome?

What causes Tatton-Brown-Rahman overgrowth syndrome?

How is Tatton-Brown-Rahman overgrowth syndrome inherited?

How rare is Tatton-Brown-Rahman overgrowth syndrome?

How is Tatton-Brown-Rahman overgrowth syndrome diagnosed?

Are there treatments for Tatton-Brown-Rahman overgrowth syndrome?

Where can I find support for Tatton-Brown-Rahman overgrowth syndrome?

What complications should we watch for in someone with Tatton-Brown-Rahman overgrowth syndrome?

How does Tatton-Brown-Rahman overgrowth syndrome affect daily life for individuals?

What is the prognosis for someone diagnosed with Tatton-Brown-Rahman overgrowth syndrome?

Are there specific specialists recommended for managing Tatton-Brown-Rahman overgrowth syndrome?