Mortality among British veterinary surgeons.

A total of 3440 veterinary surgeons resident in Britain were followed up from 1949-53 until 1975. A roughly twofold increase in mortality from suicide was observed and also a decreased mortality from respiratory diseases. There was no excess of deaths from leukaemia or other cancers as recently reported from the United States and as implied by the hypothesis that veterinary surgeons are unusually exposed to oncogenic viruses.     

Genome scan meta-analysis of schizophrenia and bipolar disorder,part II: Schizophrenia

Schizophrenia is a common disorder with high heritability and a 10-fold increase in risk to siblings of probands. Replication has been inconsistent for reports of significant genetic linkage. To assess evidence for linkage across studies, rank-based genome scan meta-analysis (GSMA) was applied to data from 20 schizophrenia genome scans. Each marker for each scan was assigned to 1 of 120 30-cM bins, with the bins ranked by linkage scores (1 = most significant) and the ranks averaged across studies (R(avg)) and then weighted for sample size (N(sqrt)[affected casess]). A permutation test was used to compute the probability of observing, by chance, each bin's average rank (P(AvgRnk)) or of observing it for a bin with the same place (first, second, etc.) in the order of average ranks in each permutation (P(ord)). The GSMA produced significant genomewide evidence for linkage on chromosome 2q (PAvgRnk<.000417). Two aggregate criteria for linkage were also met (clusters of nominally significant P values that did not occur in 1,000 replicates of the entire data set with no linkage present): 12 consecutive bins with both P(AvgRnk) and P(ord)<.05, including regions of chromosomes 5q, 3p, 11q, 6p, 1q, 22q, 8p, 20q, and 14p, and 19 consecutive bins with P(ord)<.05, additionally including regions of chromosomes 16q, 18q, 10p, 15q, 6q, and 17q. There is greater consistency of linkage results across studies than has been previously recognized. The results suggest that some or all of these regions contain loci that increase susceptibility to schizophrenia in diverse populations.     

Search for schizophrenia susceptibility variants at the HLA-DRB1 locus among a British population

Schizophrenia is a complex mental disorder with unknown aetiology. Both candidate gene and genome-wide association (GWA) studies suggest that the human leukocyte antigen (HLA) system may play a part in development of the illness, but the causal HLA variant(s) remain(s) unclear. Previous studies showed that the DRB1*0101 and DRB1*13 alleles might be associated with a high risk of schizophrenia. Therefore, the present study was undertaken to test their association with the disease by genotyping seven DRB1-tagging single nucleotide polymorphisms (SNPs) in a British population. The results showed that, of the previously reported variants that were associated with schizophrenia, the DRB1*1303 allele was the only one marginally associated with a protective effect on the illness in our sample set (χ ²?=?4.138, P?=?0.042, odds ratio (OR)?=?0.42, 95 % confidence interval (CI) 0.27–0.66). Interestingly, a significant association was found for rs424232 (χ ²?=?9.404, P?=?0.002, OR?=?0.69, 95 % CI 0.54–0.88), which is a tag SNP for the DRB1*1303 allele and located near to the NOTCH4 gene that is a schizophrenia susceptibility locus confirmed by GWA studies. Analysis with the Haploview program demonstrated that rs424232 was in complete linkage disequilibrium with rs3130297 and rs3131296 present in the NOTCH4 locus. While we have failed to confirm association of the candidate alleles in the DRB1 gene with a high risk of schizophrenia, the present work suggests that the association signal detected in the HLA class II locus may extend a relatively long distance, and more work is needed in order to identify the true causal variants within this region or nearby.