Seven autosomal recessive genes associated with juvenile and young-onset Levodopa-responsive parkinsonism have been identified. Mutations in PRKN, DJ-1, and PINK1 are associated with a rather pure parkinsonian phenotype, and have a more benign course with sustained treatment response and absence of dementia. On the other hand, Kufor-Rakeb syndrome has additional signs, which distinguish it clearly from Parkinson’s disease including supranu-clear vertical gaze palsy, myoclonic jerks, pyramidal signs, and cognitive impairment. Neurodegeneration with brain iron accumulation type I (Hallervorden-Spatz syndrome) due to mutations in PANK2 gene may share similar features with Kufor-Rakeb syndrome. Mutations in three other genes, PLA2G6 (PARK14), FBXO7 (PARK15), and Spatacsin (SPG11) also produce clinical similar phenotypes in that they presented with rapidly progressive parkinsonism, initially responsive to Levodopa treatment but later, developed additional features including cognitive decline and loss of Levodopa responsiveness. Here, using homozygosity mapping and sequence analysis in families with complex parkinsonisms, we identified genetic defects in the ATP13A2 (1 family), PLA2G6 (1 family) FBXO7 (2 families), and SPG11 (1 family). The genetic heterogeneity was surprising given their initially common clinical features. On careful review, we found the FBXO7 cases to have a phenotype more similar to PRKN gene associated parkinsonism. The ATP13A2 and PLA2G6 cases were more seriously disabled with additional swallowing problems, dystonic features, severe in some, and usually pyramidal involvement including pyramidal weakness. These data suggest that these four genes account for many cases of Levodopa responsive parkinsonism with pyramidal signs cases formerly categorized clinically as pallido-pyramidal syndrome. 3 2010 Movement Disorder Society

Robust SNP genotyping technologies and data analysis programs have encouraged researchers in recent years to use SNPs for linkage studies. Platforms used to date have been 10 K chip arrays, but the possible value of interrogating SNPs at higher densities has been considered. Here, we present a genome-wide linkage analysis by means of a 500 K SNP platform. The analysis was done on a large pedigree affected with Parkinsonian-pyramidal syndrome (PPS), and the results showed linkage to chromosome 22. Sequencing of candidate genes revealed a disease-associated homozygous variation (R378G) in FBXO7. FBXO7 codes for a member of the F-box family of proteins, all of which may have a role in the ubiquitin-proteosome protein-degradation pathway. This pathway has been implicated in various neurodegenerative diseases, and identification of FBXO7 as the causative gene of PPS is expected to shed new light on its role. The performance of the array was assessed and systematic analysis of effects of SNP density reduction was performed with the real experimental data. Our results suggest that linkage in our pedigree may have been missed had we used chips containing less than 100,000 SNPs across the genome.

Background: Complex networks are studied across many fields of science and are particularly important to understand biological processes. Motifs in networks are small connected sub-graphs that occur significantly in higher frequencies than in random networks. They have recently gathered much attention as a useful concept to uncover structural design principles of complex networks. Existing algorithms for finding network motifs are extremely costly in CPU time and memory consumption and have practically restrictions on the size of motifs.

Glaucoma is a heterogeneous group of optic neuropathies that manifests by optic nerve head cupping or degeneration of the optic nerve, resulting in a specific pattern of visual field loss. Glaucoma leads to blindness if left untreated, and is considered the second leading cause of blindness worldwide. The subgroup primary congenital glaucoma (PCG) is characterized by an anatomical defect in the trabecular meshwork, and age at onset in the neonatal or infantile period. It is the most severe form of glaucoma. CYP1B1 was the first gene genetically linked to PCG, and CYP1B1 mutations are the cause of disease in 20-100% of patients in different populations. Here, we report that LTBP2 encoding latent transforming growth factor beta binding protein 2 is a PCG causing gene, confirming results recently reported. A disease-associated locus on chromosome 14 was identified by performing whole genome autozygosity mapping in Iranian PCG families using high density single nucleotide polymorphism chips, and two disease-segregating loss of function mutations in LTBP2, p.Ser472fsX3 and p.Tyr1793fsX55, were observed in two families while sequencing candidate genes in the locus. The p.Tyr1793fsX55 mutation affects an amino acid close to the C-terminal of the encoded protein. Subsequently, LTBP2 expression was shown in human eyes, including the trabecular meshwork and ciliary processes that are thought to be relevant to the etiology of PCG.

We conclude that different and even identical PLA2G6 mutations may cause neurodegenerative diseases with heterogeneous clinical manifestations, including INAD, NBIA and dystonia-parkinsonism.

Latent transforming growth factor (TGF) beta-binding protein 2 (LTBP2) is an extracellular matrix (ECM) protein that associates with fibrillin-1 containing microfibrils. Various factors prompted considering LTBP2 in the etiology of isolated ectopia lentis and associated conditions such as Weill-Marchesani syndrome (WMS) and Marfan syndrome (MFS). LTBP2 was screened in 30 unrelated Iranian patients. Mutations were found only in one WMS proband and one MFS proband. Homozygous c.3529G>A (p.Val1177Met) was shown to cause autosomal recessive WMS or WM-like syndrome by several approaches, including homozygosity mapping. Light, fluorescent, and electron microscopy evidenced disruptions of the microfibrillar network in the ECM of the proband's skin. In conjunction with recent findings regarding other ECM proteins, the results presented strongly support the contention that anomalies in WMS patients are due to disruptions in the ECM. Heterozygous c.1642C >T (p.Arg548*) possibly contributed to MFS-related phenotypes, including ocular manifestations, mitral valve prolapse, and pectus excavatum, but was not cause of MFS.

A halothermotolerant Gram-positive spore-forming bacterium was isolated from petroleum reservoirs in Iran and identified as Bacillus licheniformis sp. strain ACO1 by phenotypic characterization and 16S rRNA analysis. It showed a high capacity for bioemulsifier production and grew up to 60 degrees C with NaCl at 180 g l(-1). The optimum NaCl concentration, pH and temperature for bioemulsifier production were 4% (w/v), 8.0, and 45 degrees C, respectively. Although ACO1 did not utilize hydrocarbons, it had a high emulsifying activity (E (24) = 65 +/- 5%) on different hydrophobic substrates. Emulsification was optimal while growing on yeast extract as the sole carbon source and NaNO(3) as the nitrogen source. The efficiency of the residual oil recovery increased by 22% after in situ growth of B. licheniformis ACO1 in a sand-pack model saturated with liquid paraffin.

Nerve tissue engineering requires suitable precursor cells as well as the necessary biochemical and physical cues to guide neurite extension and tissue development. An ideal scaffold for neural regeneration would be both fibrous and electrically conductive. We have contrasted the growth and neural differentiation of mouse embryonic stem cells on three different aligned nanofiber scaffolds composed of poly L: -lactic acid supplemented with either single- or multi-walled carbon-nanotubes. The addition of the nanotubes conferred conductivity to the nanofibers and promoted mESC neural differentiation as evidenced by an increased mature neuronal markers expression. We propose that the conductive scaffold could be a useful tool for the generation of neural tissue mimics in vitro and potentially as a scaffold for the repair of neural defects in vivo.