Rare Nephrology News

Disease Profile

Nicolaides-Baraitser syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

<1 / 1 000 000

US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

NCBRS; Intellectual disability-sparse hair-brachydactyly syndrome


Congenital and Genetic Diseases; Nervous System Diseases


Nicolaides-Baraitser syndrome (NCBRS) is a very rare condition characterized by severe intellectual disability and various physical features. Signs and symptoms may include seizures, short stature, sparse hair, distinctive facial characteristics, short fingers and toes (brachydactyly), and prominent joints in the fingers and toes (interphalangeal joints). Features of the condition can worsen over time. NCBRS is caused by changes (mutations) in the SMARCA2 gene and is inherited in an autosomal dominant manner. All cases reported to date have been sporadic, occurring in people with no family history of NCBRS.[1]


Nicolaides-Baraitser syndrome (NCBRS) is typically characterized by intellectual disability, seizures, short stature, sparse hair, distinctive facial features, short fingers and toes (brachydactyly), and prominent joints of the fingers and toes (called interphalangeal joints). Some features of the condition may vary among affected people.[1]

All people with NCBRS have intellectual disability. In most cases it is severe, but in some cases it may be moderate or mild. Language is particularly limited, with at least 30% of affected people never developing speech. Major motor milestones such as sitting and walking are usually not very delayed. People with NCBRS are often happy and friendly, but may have temper tantrums or periods of aggression. Some people have some symptoms of autism spectrum disorder. Epilepsy occurs in about 2/3 of affected people. The type of seizures that occur can vary.[1]

Facial characteristics are usually not recognized in younger affected people. They may include a triangular-shaped face; prominent eyelashes; a nose with a broad base, thick nostrils, and upturned tip; a broad philtrum; and wide mouth. The palpebral fissures (width of the eyes) are sometimes narrow and/or downslanting. As people with NCBRS age, the amount of subcutaneous fat tissue tends to decrease, making the skin below the eyes sagging and wrinkled, especially at the cheeks when smiling. However, some affected people retain full cheeks. Facial characteristics typically become more pronounced with increasing age. In some affected adults, the lower third of the face becomes markedly broad.[1]

Sparse scalp hair is a major feature of NCBRS and is present in almost all affected people. It often gradually worsens with age, but in some people it improves over time. Skin is usually wrinkled and more noticeable in the distal limbs. Teeth may be widely spaced, and eruption of teeth (baby or adult) may be delayed. While the hands and feet usually appear normal at birth, the interphalangeal joints become prominent in the majority of affected people. Bone age can vary, and osteoporosis is not uncommon.[1]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Abnormality of the metacarpal bones
Abnormality of the long bone of hand
Hair loss
Anteverted nares
Nasal tip, upturned
Upturned nasal tip
Upturned nose
Upturned nostrils

[ more ]

Difficulty finding words
Losing words
Loss of words

[ more ]

Short fingers or toes
Echoing another person's speech
Everted lower lip vermilion
Drooping lower lip
Outward turned lower lip

[ more ]

Global developmental delay
High, narrow palate
Narrow, high-arched roof of mouth
Narrow, highly arched roof of mouth

[ more ]

Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific

[ more ]

Joint dislocation
Joint dislocations
Recurrent joint dislocations

[ more ]

Long philtrum
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference

[ more ]

Inability to speak

[ more ]

Short palm
Smooth philtrum
Sparse hair
Specific learning disability
Thick nasal alae
Thin vermilion border
Decreased volume of lip
Thin lips

[ more ]

Triangular face
Face with broad temples and narrow chin
Triangular facial shape

[ more ]

Wide mouth
Broad mouth
Large mouth

[ more ]

30%-79% of people have these symptoms
Abnormal hair pattern
Abnormal distribution of hair
Narrow opening between the eyelids
Broad distal phalanx of finger
Broad outermost finger bone
Clubbing of toes
Undescended testes
Undescended testis

[ more ]

Curly eyelashes
Epileptic spasm
Excessive wrinkled skin
Generalized non-motor (absence) seizure
Brief seizures with staring spells
Highly arched eyebrow
Arched eyebrows
Broad, arched eyebrows
High, rounded eyebrows
High-arched eyebrows
Thick, flared eyebrows

[ more ]

Long eyelashes
Increased length of eyelashes
Unusually long eyelashes

[ more ]

Narrow nasal bridge
Nasal Bridge, Narrow
Nasal bridge, thin
Narrow bridge of nose

[ more ]

Sandal gap
Gap between 1st and 2nd toes
Gap between first and second toe
Increased space between first and second toes
Sandal gap between first and second toes
Wide space between 1st, 2nd toes
Wide space between first and second toes
Wide-spaced big toe
Widely spaced 1st-2nd toes
Widely spaced first and second toes
Widened gap 1st-2nd toes
Widened gap first and second toe

[ more ]

Severe short stature
Proportionate dwarfism
Short stature, severe

[ more ]

Short palpebral fissure
Short opening between the eyelids
Status epilepticus
Repeated seizures without recovery between them
Wide intermamillary distance
Wide-spaced nipples
Widely spaced nipples
Widely-spaced nipples

[ more ]

5%-29% of people have these symptoms
Abnormality of cardiovascular system morphology
Abnormality of epiphysis morphology
Abnormal shape of end part of bone
Accelerated skeletal maturation
Advanced bone age
Early bone maturation

[ more ]

Delayed skeletal maturation
Delayed bone maturation
Delayed skeletal development

[ more ]

Downslanted palpebral fissures
Downward slanting of the opening between the eyelids
1%-4% of people have these symptoms
Short stature
Decreased body height
Small stature

[ more ]



Nicolaides-Baraitser syndrome (NCBRS) is caused by mutations in the SMARCA2 gene, which is located on the small arm of chromosome 9. All mutations that have been identified in affected people have been either missense mutations or in-frame deletions.

There may be some correlations between specific types of mutations and some of the features that result (called genotypephenotype correlations), but more studies are needed to draw definitive conclusions.[1]


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

    Social Networking Websites

      Organizations Providing General Support

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

        • Genetics Home Reference (GHR) contains information on Nicolaides-Baraitser syndrome. This website is maintained by the National Library of Medicine.

          In-Depth Information

          • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
          • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Nicolaides-Baraitser syndrome. Click on the link to view a sample search on this topic.


            1. Sousa SB, Hennekam RC; Nicolaides-Baraitser Syndrome International Consortium. Phenotype and genotype in Nicolaides-Baraitser syndrome. Am J Med Genet C Semin Med Genet. September, 2014; 166C(3):302-314.
            2. Sousa SB, et. al. Nicolaides-Baraitser syndrome: Delineation of the phenotype. Am J Med Genet A. August, 2009; 149A(8):1628-1640.
            3. Omar Abdul-Rahman. Nicolaides-Baraitser Syndrome. GeneReviews. October 15, 2015; https://www.ncbi.nlm.nih.gov/books/NBK321516/.

            Rare Nephrology News