Dynamic mutation

Dynamic mutation is a type of genetic mutation that involves the expansion of nucleotide repeats within certain genes. This expansion can lead to various genetic disorders, depending on the gene affected and the extent of the expansion.

Overview

Dynamic mutations occur when the number of repeated nucleotides in a gene increases. These repeats are often of the trinucleotide variety, meaning they consist of three nucleotides. The most common types of trinucleotide repeats involved in dynamic mutations are C, G, and A (CGA) or C, A, and G (CAG).

Disorders

Dynamic mutations are responsible for a number of genetic disorders. These include:

• Fragile X syndrome: This is caused by a dynamic mutation in the FMR1 gene, which leads to intellectual disability and physical abnormalities.
• Huntington's disease: This is caused by a dynamic mutation in the HTT gene, which leads to progressive brain damage.
• Myotonic dystrophy: This is caused by a dynamic mutation in the DMPK gene, which leads to muscle weakness and stiffness.

Mechanism

The mechanism of dynamic mutation involves the replication of DNA. During replication, the DNA polymerase enzyme can slip and mispair the nucleotides, leading to the addition of extra repeats. Over time, these extra repeats can accumulate and expand, leading to the manifestation of genetic disorders.

Diagnosis and Treatment

Diagnosis of disorders caused by dynamic mutations often involves genetic testing to identify the presence of expanded repeats. Treatment typically involves managing the symptoms of the disorder, as there is currently no cure for these conditions.

See Also

• Genetic mutation
• Nucleotide
• Gene
• Genetic disorder
• Fragile X syndrome
• Huntington's disease
• Myotonic dystrophy