Absence of linkage between familial amyotrophic lateral sclerosis and copper chaperone for the superoxide dismutase gene locus in two Italian pedigrees

Association analysis between Alzheimer's disease and the Nicastrin gene polymorphisms

The biological study of the Nicastrin protein shows its crucial role in the pathogenesis of Alzheimer's disease (AD). We tested the hypothesis that the Nicastrin (NCSTN) gene might be genetically associated with AD. The association analysis of two single nucleotide polymorphisms (SNPs) in the coding region (cSNPs) of NCSTN were performed in an Italian population. No evidence of association was obtained between the two SNPs investigated in sporadic and familial AD cases under the stratification of currently known genetic risk factors including the apolipoprotein E (APOE), the presenilins and the beta-amyloid precursor protein. The result suggests no apparent synergic interaction between the NCSTN and APOE epsilon 4 in the risk to develop the late onset sporadic form of AD. But considering its biological effects, the result can not exclude the NCSTN as candidate for genetic factor in AD. Further genetic study of the NCSTN would be necessary to evaluate the potential genetic involvement in AD.

Association study of the 5-hydroxytryptamine(6) receptor gene in Alzheimer's disease

Serotonergic (5-hydroxytryptamine; 5-HT) transmission has been implicated in the pathogenesis of Alzheimer's disease (AD). A coding single nucleotide polymorphism 267 (C/T) in the 5-HT(6) receptor gene was previously reported as a susceptibility factor for AD. An extensive replication study was performed using our data set including sporadic and familial cases. No significant association between the 5-HT(6) receptor gene and AD was obtained with or without the stratification of apolipoprotein E epsilon 4 status. Our result suggests that the 267C allele of the 5-HT(6) receptor gene may not be a genetic risk factor for AD.

Human CCS gene: genomic organization and exclusion as a candidate for amyotrophic lateral sclerosis (ALS)

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive lethal disorder of large motor neurons of the spinal cord and brain. In approximately 20% of the familial and 2% of sporadic cases the disease is due to a defect in the gene encoding the cytosolic antioxidant enzyme Cu, Zn-superoxide dismutase (SOD1). The underlying molecular defect is known only in a very small portion of the remaining cases and therefore involvement of other genes is likely. As SOD1 receives copper, essential for its normal function, by the copper chaperone, CCS (Copper Chaperone for SOD), we considered CCS as a potential candidate gene for ALS.

RESULTS

We have characterized the genomic organization of CCS and determined exon-intron boundaries. The 823 bp coding region of the CCS is organized in 8 exons. We have evaluated involvement of the CCS in ALS by sequencing the entire coding region for mutations in 20 sporadic ALS patients.

CONCLUSIONS

No causative mutations for the ALS have been detected in the CCS gene in 20 sporadic ALS patients analyzed, but an intragenic single nucleotide polymorphism has been identified.

Familial amyotrophic lateral sclerosis

The increasing complexity of the pathways implicated in the pathogenesis of familial amyotrophic lateral sclerosis (ALS) has stimulated intensive research in many directions. Genetic analysis of familial ALS has yielded six loci and one disease gene (SOD1), initially suggesting a role for free radicals in the disease process, although the mechanisms through which the mutant exerts toxicity and results in selective motor neuron death remain uncertain. Numerous studies have focused on structural elements of the affected cell, emphasizing the role of neurofilaments and peripherin and their functional disruption in disease. Other topics examined include cellular homeostasis of copper and calcium, particularly in the context of oxidative stress and the processes of protein aggregation, glutamate excitotoxicity, and apoptosis. It has become evident that there is considerable interplay between these mechanisms and, as the role of each is established, a common picture may emerge, enabling the development of more targeted therapies. This study discusses the main areas of investigation and reviews the findings.