Association between the CCR5 32-bp deletion allele and late onset of schizophrenia.
OBJECTIVE
The 32-bp deletion allele in chemokine receptor CCR5 has been associated with several immune-mediated diseases and might be implicated in schizophrenia as well.


METHODS
The authors genotyped DNA samples from 268 schizophrenia patients and 323 healthy subjects. Age at first admission to a psychiatric hospital department served as a measure of disease onset.


RESULTS
Patients and comparison subjects differed marginally in their genotype distribution, with a slightly higher frequency of the deletion allele seen in the patients. The authors found the deletion allele to be associated with higher age at first admission. After age at first admission was analyzed as a continuous variable, it was dichotomized using 40 years as the cutoff. With this approach the authors found that genotype distributions of patients with age at first admission above the cutoff (possible cases of late-onset schizophrenia) and healthy subjects differed significantly. This was reflected in an increased frequency of the deletion allele in the patient subgroup. Patients with ages at first admission below and above 40 years significantly differed in distribution of genotypes and alleles, with an overrepresentation of the deletion allele in the latter subgroup of patients.


CONCLUSIONS
These findings suggest that the CCR5 32-bp deletion allele is a susceptibility factor for schizophrenia with late onset. Alternatively, the CCR5 32-bp deletion allele may act as a modifier by delaying the onset of schizophrenia without affecting the disease susceptibility.
Rasmussen
Henrik Berg
HB
Research Institute of Biological Psychiatry, H:S Sct. Hans Hospital, DK-4000 Roskilde, Denmark. henrik.berg.rasmussen@shh.hosp.dk
Timm
Sally
S
Wang
August G
AG
Søeby
Karen
K
Lublin
Henrik
H
Fenger
Mogens
M
Hemmingsen
Ralf
R
Werge
Thomas
T
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D002648:Child; D002872:Chromosome Deletion; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D019656:Loss of Heterozygosity / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D019713:Receptors, CCR5 / Q000235:genetics*; D012559:Schizophrenia / Q000175:diagnosis / Q000235:genetics*
D019713:Receptors, CCR5