Nicolaides–Baraitser syndrome

Nicolaides–Baraitser syndrome (NCBRS) is a rare genetic condition caused by de novo missense mutations in the SMARCA2 gene and has only been reported in less than 100 cases worldwide.^[1] NCBRS is a distinct condition and well recognizable once the symptoms have been identified.

The differential includes Coffin–Siris syndrome.

Symptoms[edit | edit source]

The most common symptoms of Nicolaides–Baraitser syndrome are mild to severe developmental delays with absent or limited speech, seizures, short stature, sparse hair, typical facial characteristics, brachydactyly, and prominent finger joints and broad distal phalanges.^[2]

Major Features of NCBRS[edit | edit source]

Mild prenatal growth retardation
Moderate postnatal growth retardation
Mild to severe developmental delay
Severely impaired speech
Seizures
Microcephaly
Sparse hair
Progressive skin wrinkling
Thick, anteverted alae nasi
Long and broad philtrum
Large mouth
Thin upper and thick lower vermilion
Progressive prominence of distal phalanges
Progressive prominence of inter-phalangeal joints
Scoliosis
Short metacarpals–metatarsals

Cause[edit | edit source]

This condition occurs via mutations in the SMARCA2 gene. In rare instances this condition can occur via a mutation in the ARID1B gene.^[3]

History[edit | edit source]

Paola Nicolaides was a pediatric neurologist and Michael Baraitser a clinical geneticist, both working in Great Ormond Street Hospital for Children in London. They saw a young girl with an unusual combination of signs and symptoms, and thought this to be a recognizable entity. They published this in a medical journal in 1993.^[4] Other authors later suggested to name the entity after the authors who had first described it.^[5]