Autosomal dominant spastic paraplegia in four generations of Yakut family linked to dynamin 2 mutation

The article presents the results of a clinical and genetic study of a Yakut family with hereditary spastic paraplegia (HSP). Patients with clinically diagnosed HSP and healthy family members were studied. The disease is clinically characterized as a progressive spastic paraplegia of the lower extremities concomitant peripheral neuropathy in advanced case. The methods of exome sequencing of the entire genome, molecular modeling of dynamin-2 and experimental reproduction of key elements of the HSP pathogenesis have been applied. Genetic analysis revealed a novel missense c.2155C> T, p.R719W mutation in the highly conserved GTP-effector domain of the dynamin-2 gene (DNM2). In experiments on HeLa cells, it was shown that mutant dynamin-2 affected endocytosis process. In-silico modeling determined that the identified mutation is located in the DNM2 bundle-signaling element and potentially disrupts the assembly and functional properties of the protein. Testing of this mutation in other Yakut families with HSP showed a negative result, which once again confirms the genetic heterogeneity of this pathology.