SNP Shot: Genomic Insights

Mitochondrial membrane protein-associated neurodegeneration (MPAN) is a neurological disease that generally starts in childhood or young adulthood and progressively worsens.

A common initial symptom of MPAN is difficulty walking. As the disease advances, individuals typically experience other movement-related issues like muscle stiffness (spasticity) and involuntary muscle contractions (dystonia). Many individuals with MPAN exhibit parkinsonism, characterized by slowed movement (bradykinesia), muscle rigidity, tremors, and postural instability.

Further neurological complications associated with MPAN include optic atrophy (degeneration of optic nerves), leading to vision impairment; dysarthria (speech difficulties); dysphagia (swallowing difficulties); and, in advanced stages, incontinence (loss of bowel or bladder control). Furthermore, affected individuals may develop dementia (cognitive decline) and psychiatric symptoms such as behavioral disturbances, mood instability, hyperactivity, and depression.

A key feature of MPAN is the accumulation of iron in specific brain areas. Due to this iron buildup, MPAN belongs to a group of disorders called neurodegeneration with brain iron accumulation (NBIA).

Inheritance:

MPAN follows an autosomal recessive inheritance pattern. This means that an individual must inherit two mutated copies of the responsible gene, one from each parent, to develop the condition. The parents, who each carry one copy of the mutated gene, are typically unaffected and do not show symptoms.