ICAM G241A polymorphism and soluble ICAM-1 serum levels: evidence for an active immune process in schizophrenia.
OBJECTIVE
We have previously reported reduced serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in schizophrenic patients. A single-nucleotide polymorphism (SNP) of the ICAM-1 gene was described at position 241. The G-->A SNP results in a nonsynonymous amino acid exchange of the ICAM-1 protein, and the A allele was shown to be also associated with several immunological disorders like rheumatoid arthritis.


METHODS
We investigated 70 schizophrenic patients and 128 unrelated healthy control persons regarding the relationship between the serum levels of sICAM-1 and the ICAM-1 G214A polymorphism.


RESULTS
We were able to replicate our previous finding of reduced sICAM-1 levels in schizophrenia. Healthy control persons carrying the polymorphic A allele showed markedly lower sICAM-1 serum levels than carriers of the homozygous GG wild type (p < 0.004). In contrast, no significant difference in the sICAM-1 serum levels were seen regarding the G241A genotype distribution in schizophrenic patients.


CONCLUSIONS
We hypothesize that the biochemical effect of the G241A SNP is masked in schizophrenic patients, indicating a disease-related mechanism leading to reduced levels of sICAM-1 in schizophrenia.
Kronig
Holger
H
Psychiatric Hospital, Ludwig-Maximilian University Munich, Munich, Germany.
Riedel
Michael
M
Schwarz
Markus J
MJ
Strassnig
Martin
M
Moller
Hans-Jurgen
HJ
Ackenheil
Manfred
M
Muller
Norbert
N
D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution / Q000235:genetics / Q000276:immunology; D001327:Autoimmune Diseases / Q000097:blood / Q000235:genetics / Q000276:immunology; D002448:Cell Adhesion / Q000235:genetics / Q000276:immunology; D004252:DNA Mutational Analysis; D015536:Down-Regulation / Q000235:genetics / Q000276:immunology; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005820:Genetic Testing; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood / Q000235:genetics* / Q000276:immunology*; D016177:Macrophage-1 Antigen / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012559:Schizophrenia / Q000097:blood / Q000235:genetics* / Q000276:immunology*
D016177:Macrophage-1 Antigen; D018799:Intercellular Adhesion Molecule-1