Acknowledgement of Childhood-onset neurodegeneration with brain atrophy (CONDBA) has not been added yet.

CONDBA has been recently described in two clinical reports in the literature. In the first one (Edvardson et al. 2017) 7 individuals were identified and in the second (Toro et al. 2018) another 4. These data should be taken with caution in terms of the actual prevalence of the disease. This disorder has recently been described as new medical entity and this numbers can be an underrepresentation.

Name	Abbreviation
UBTF-Related Neurodegenerative Disorder	CONDBA

CONDBA is caused by a de novo mutation in the UBTF gene that creates a Glu210Lys change in the UBF protein.  The gene UBTF provides the blueprint for the production of the protein UBF. The UBF protein stimulates the production of a nucleic acid molecule known as ribosomal RNA or rRNA. This ribosomal RNA is further processed to create a structure call the ribosome. These ribosomes are in charge of reading the information present in our genes and translate it into its respective protein. The particular alteration in the UBF protein (Glu210Lys o E210K) that causes the neurodegenerative disorder, increases the ability of UBF to produce ribosomal RNA. How this in turn causes the neurodegeneration it is not fully understood. It has been proposed that an excess of ribosomal RNA could be toxic for the nerve cells and make them die.

Most of the children presented normal developmental milestones until the onset of the disease, which occurred between 2.5 to 7 years of age. The loss of the motor abilities usually precedes the loss of cognitive or social skills, but in some cases the cognitive impairment might appear first.

The first motor symptoms are loss of muscle tone or strength (hypotonia), difficulty walking (walking uncoordinated or gait ataxia) and difficulty to talk due to weakness of the muscles involved in the speech (dysarthria). As the disease progresses the motor function worsens and other symptoms appear: parkinsonism or spasms of the muscles, loss of ability to maintain the posture or walking and feeding difficulties.

Language difficulties to both communicate and understand are the first signs of cognitive dysfunction. It can progress to severe difficulty to communicate with both speech and body language and ultimately lead to the inability to understand verbal commands.

Some children have been reported to suffer from a loss of social skills presenting autistic features. Seizures may also present.

The presence of the E210K alteration in the UBTF gene can help confirm a CONDBA diagnosis.

A genetic test for the UBTF gene to identify the E120K alteration.

Unfortunately, there is not current treatment for this condition.

People with CONDBA suffer from a profound decline in their self-care abilities upon progression of the disease, needing assistance from family members or professionals on a daily basis.

Tips or Suggestions of Childhood-onset neurodegeneration with brain atrophy (CONDBA) has not been added yet.

Edvardson, S., et al. (2017). "Heterozygous De Novo UBTF Gain-of-Function Variant Is Associated with Neurodegeneration in Childhood." Am J Hum Genet 101(2): 267-273.

Toro, C., et al. (2018). "A recurrent de novo missense mutation in UBTF causes developmental neuroregression." Hum Mol Genet 27(7): 1310.