Expanded CAG/CTG repeats in schizophrenia. A study of clinical correlates.
BACKGROUND
Schizophrenia is associated with expanded CAG/CTG trinucleotide repeats. We wished to determine whether the presence of such expansions correlated with specific subsyndromes or other clinical features of schizophrenia.


METHODS
Seventy patients from England and Wales and 44 patients from Portugal with a DSM-III-R diagnosis of schizophrenia were rated on the OPCRIT checklist. Patient's maximum CAG/CTG repeat length was measured using repeat expansion detection (RED). Significant differences were sought for repeat lengths in subjects categorised according to dimensional and categorical schizophrenia subsyndromes, affective episodes, individual symptoms, and a range of demographic variables.


RESULTS
Maximum CAG/CTG repeat length did not differ significantly for any of the clinical or demographic variables studied.


CONCLUSIONS
There are no subsyndromes or other clinical features of schizophrenia associated with CAG/CTG repeat expansion. Therefore, the identification of the gene(s) that contain expanded CAG/CTG repeats and which are associated with schizophrenia is unlikely to be facilitated at present by using any subsyndromes of schizophrenia as phenotypes.
Cardno
A G
AG
Department of Psychological Medicine, University of Wales College of Medicine, Health Park, Cardiff, UK.
Murphy
K C
KC
Jones
L A
LA
Guy
C A
CA
Asherson
P
P
De Azevedo
M H
MH
Coelho
I M
IM
de Macedo e Santos
A J
AJ
Pato
C N
CN
McGuffin
P
P
Owen
M J
MJ
O'Donovan
M C
MC
D000328:Adult; D003431:Cross-Cultural Comparison; D004739:England; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011174:Portugal; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000145:classification / Q000175:diagnosis / Q000235:genetics*; D013577:Syndrome; D018911:Trinucleotide Repeats / Q000235:genetics*; D014852:Wales