Hereditary spastic paraplegia (HSP) is a neurodegenerative disease characterized by lower-limb spasticity, hyperreflexia, progressive spastic gait abnormalities, and an extensor-plantar response. It is genetically very heterogeneous, with 28 Human Genome Organisation (HUGO)-approved IDs in the database (last search: August 8, 2004). Following the identification of the SPG6 gene, NIPA1, we have identified two novel mutations, c.316G>C and c.316G>A, in two independent Chinese families linked to the SPG6 locus. These two mutations would cause a p.G106R substitution, and cosegregated with the disease. Structural predictions suggest that p.G106 is located in the third transmembrane domain of the protein, and that the mutant p.G106R disrupts this structure, causing the intramembrane loop to descend into the cytoplasm. Our results identify two novel mutations responsible for HSP and suggest that c.316 of theNIPA1 gene may be a mutational hotspot.
We perform an exhaustive, taxon by taxon, comparison of the branchings in the composition vector trees (CVTrees) inferred from 432 prokaryotic genomes available on 31 December 2006, with the bacteriologists' taxonomy--primarily the latest online Outline of the Bergey's Manual of Systematic Bacteriology. The CVTree phylogeny agrees very well with the Bergey's taxonomy in majority of fine branchings and overall structures. At the same time most of the differences between the trees and the Manual have been known to biologists to some extent and may hint at taxonomic revisions. Instead of demonstrating the overwhelming agreement this paper puts emphasis on the biological implications of the differences.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.