Variants Cause Spastic Paraplegia Associated with Cerebral Hypomyelination

Oculodentodigital dysplasia is an autosomal dominant disorder due to variants characterized by dysmorphic features. Neurologic symptoms have been described in some patients but without a clear neuroimaging pattern. To understand the pathophysiology underlying neurologic deficits in oculodentodigital dysplasia, we studied 8 consecutive patients presenting with hereditary spastic paraplegia due to variants. Clinical disease severity was highly variable. Cerebral MR imaging revealed variable white matter abnormalities, consistent with a hypomyelination pattern, and bilateral hypointense signal of the basal ganglia on T2-weighted images and/or magnetic susceptibility sequences, as seen in neurodegeneration with brain iron accumulation diseases. Patients with the more prominent basal ganglia abnormalities were the most disabled ones. This study suggests that -related hereditary spastic paraplegia is a complex neurodegenerative disease affecting both the myelin and the basal ganglia. variants should be considered in patients with hereditary spastic paraplegia presenting with brain hypomyelination, especially if associated with neurodegeneration and a brain iron accumulation pattern

Isolation and development microsatellite markers in the Pygocentrus nattereri (Kner, 1858) (Characiformes, Serrasalminae), an important freshwater fish in the Amazon

The red-bellied piranha belongs to the Pygocentrus genus, and is a representative of the Serrasalmidae family. The P. nattereri is the most abundant species in the floodplain of the Solimões-Amazonas river system. In the present work, 11 microsatellite loci were developed and used to investigate the genetic variation on 35 wild individuals. The number of alleles per locus ranged from 3 to 15, with an average of 8.2. The observed and expected heterozygosity values varied from 0.300 to 0.824 (mean 0.559) and 0.261 to 0.779 (mean 0.571), respectively. Only one loci (PN11) deviated significantly from Hardy-Weinberg equilibrium after Bonferroni correction. No significant linkage disequilibrium was detected. These polymorphic markers should be useful tools for assessing population genetics of P. nattereri, an overfished species in the Amazon varzea lakes that is most appreciated as a food item. © 2011 Springer Science+Business Media B.V