SNP Shot: Genomic Insights

Autosomal recessive axonal neuropathy with neuromyotonia is a condition impacting the peripheral nerves. These nerves link the brain and spinal cord to muscles and sensory cells, which are responsible for sensing touch, pain, temperature, and sound.

A key feature, axonal neuropathy, arises from damage to axons. Axons are the part of the peripheral nerves that are extensions of nerve cells (neurons) and carry nerve signals. This damage in autosomal recessive axonal neuropathy with neuromyotonia mainly results in worsening muscle weakness and muscle loss (atrophy) in the feet, legs, and hands. This weakness might be more noticeable during physical activity (exercise intolerance). This can lead to an abnormal walk (gait), frequent falls, and fixed, deformed joints (contractures) in the hands and feet. Some individuals may also experience reduced sensitivity to touch, temperature, or pain, particularly in the lower arms or legs.

Neuromyotonia, also known as Isaac syndrome, is another aspect of this condition. It's caused by excessive activity (hyperexcitability) in the peripheral nerves. This leads to slow muscle relaxation after voluntary muscle tightening (contraction), muscle cramps, and involuntary, wave-like muscle movements (myokymia).

Inheritance:

The disorder follows an autosomal recessive inheritance pattern. This means that both copies of the responsible gene in each cell must have mutations for the condition to manifest. Individuals with autosomal recessive conditions inherit one mutated gene copy from each parent, who are usually carriers and do not exhibit symptoms themselves.