Analysis of heavy neurofilament subunit gene polymorphism in Russian patients with sporadic motor neuron disease (MND)

Motor neuron disease (MND) results in the selective degeneration of motor neurons in the cerebral cortex, brain stem and spinal cord. The most common form of MND is amyotrophic lateral sclerosis (ALS). MND is complex and many genetic systems may be involved in the pathogenesis of this disease. Pathological and animal studies implicate neurofilament involvement in MND. The heavy subunit (NEFH) tail domain contains a repeated motif. In humans, there are two common variants: the 45 motif repeats long allele (L) and 44 motif repeats short allele (S). Previous studies have shown that the NEFH tail may be involved in the pathogenesis of MND. To investigate whether the L/S genotypes of the NEFH gene are associated with MND, we studied the frequency of L and S alleles in sporadic MND patients and a control population from Moscow. We observed a difference in SS genotype frequency between the control population and sporadic MND patients from Moscow. It was established that the SS genotype is sufficiently higher in sporadic MND patients. Moreover, we determined that patients with the SS genotype have the highest value of loss of the total clinical score. In summary, we conclude that the NEFH gene is involved in the pathogenesis of sporadic MND. The SS genotype represents a risk factor for the development and progression of sporadic MND in the Moscow population.