MBD5 gene

methyl-CpG binding domain protein 5

The MBD5 gene is one of a family of genes called the methyl-CpG-binding domain (MBD) genes. These genes provide instructions for making proteins that help regulate gene activity (expression) by modifying chromatin, the complex of DNA and protein that packages DNA into chromosomes. The MBD5 protein is likely involved in regulating gene expression and controlling the production of proteins that are involved in neurological functions such as learning, memory, and behavior. The MBD5 protein also seems to play a role in the growth and division (proliferation) and maturation (differentiation) of various types of cells.

Mutations in the MBD5 gene have been found to cause MBD5-associated neurodevelopmental disorder (MAND). MAND is a condition that affects neurological and physical development from birth. Affected individuals often have intellectual disability, developmental delay, impaired speech, sleep problems, distinctive facial features, and mild hand and foot abnormalities. Most people with MAND also have behavior problems similar to autism spectrum disorder, a developmental condition that affects communication and social interaction.

Some MBD5 gene mutations that cause MAND delete large segments of the MBD5 gene or result in the production of an altered protein with no function. These mutations affect one copy of the gene in each cell. As a result, there is less MBD5 protein available to regulate the expression of certain genes, leading to uncontrolled protein production. Proteins that play a role in neurological functions are particularly affected, which helps explain why MAND impacts brain development and behavior.

Additionally, an extra copy of the MBD5 gene or a loss of the whole gene in each cell can cause MAND. In these cases, MAND results from abnormal copying (duplication) or removal (deletion) of a small piece of the long (q) arm of chromosome 2 at position 2q23.1. The duplicated or deleted segments can vary in size but always include the MBD5 gene, and often additional genes. Researchers believe that MBD5 gene changes underlie most of the signs and symptoms of MAND. Features of the condition generally do not differ based on the genetic cause, although they can vary between individuals.

Cytogenetic Location: 2q23.1, which is the long (q) arm of chromosome 2 at position 23.1

Molecular Location: base pairs 148,021,011 to 148,516,923 on chromosome 2 (Homo sapiens Annotation Release 109, GRCh38.p12) (NCBI)

Cytogenetic Location: 2q23.1, which is the long (q) arm of chromosome 2 at position 23.1
  • methyl-CpG-binding domain protein 5
  • methyl-CpG-binding protein MBD5