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As suggested by several studies, abnormal sensory gating measured by the P50 paradigm could be an endophenotype predisposing to schizophrenia. In a previous work, we have shown a significant association between the presence of at least one -2?bp deletion located within exon 6 of the CHRNA7-like gene and the P50 abnormality in the general population. A recent study involved polymorphisms located in the core promoter region of the CHRNA7 gene as risk factors for the P50 inhibitory deficit. Screening for promoter variants in a large population of schizophrenic patients (n=111) and control subjects (85), for whom auditory-evoked potentials had been recorded did not allow us to replicate these results. By contrast, we showed a significant association between the -194 C allele and a T/C ratio <0.45, thus demonstrating a protective effect of this variant for the sensory gating deficit. Such conflicting results can be reconciled if we consider that the -194 C polymorphism has no causative effect, but is in linkage disequilibrium with other causal variations for the P50 sensory gating deficit, and that different alleles are in disequilibrium in different populations.Molecular Psychiatry (2004) 9, 320-322. doi:10.1038/sj.mp.4001443 Published online 21 October 2003 [ABSTRACT FROM AUTHOR]

Two polymorphic markers were identified on the desmoglein 1 gene which encodes the autoantigen targeted by pathogenic antibodies in pemphigus foliaceus (PF), a cutaneous autoimmune blistering disease. The first marker, made of a variant haplotype of five mis-sense mutations located on the part of the gene encoding the fourth and fifth extracellular domains of the protein, is not associated with the disease. The second marker consists of a single silent T to C transition at position 809 and was found to be significantly more frequent (P = 0.015) in Caucasian PF patients (n = 36) than in controls (n = 98). Thus, pemphigus foliaceus constitutes another example of autoimmune disease in which the autoantigen polymorphism contributes to disease susceptibility. Genes and Immunity (2001) 2 , 41–43. [ABSTRACT FROM AUTHOR]