microRNA expression in the prefrontal cortex of individuals with schizophrenia and schizoaffective disorder.
BACKGROUND
microRNAs (miRNAs) are small, noncoding RNA molecules that are now thought to regulate the expression of many mRNAs. They have been implicated in the etiology of a variety of complex diseases, including Tourette's syndrome, Fragile x syndrome, and several types of cancer.


RESULTS
We hypothesized that schizophrenia might be associated with altered miRNA profiles. To investigate this possibility we compared the expression of 264 human miRNAs from postmortem prefrontal cortex tissue of individuals with schizophrenia (n = 13) or schizoaffective disorder (n = 2) to tissue of 21 psychiatrically unaffected individuals using a custom miRNA microarray. Allowing a 5% false discovery rate, we found that 16 miRNAs were differentially expressed in prefrontal cortex of patient subjects, with 15 expressed at lower levels (fold change 0.63 to 0.89) and 1 at a higher level (fold change 1.77) than in the psychiatrically unaffected comparison subjects. The expression levels of 12 selected miRNAs were also determined by quantitative RT-PCR in our lab. For the eight miRNAs distinguished by being expressed at lower microarray levels in schizophrenia samples versus comparison samples, seven were also expressed at lower levels with quantitative RT-PCR.


CONCLUSIONS
This study is the first to find altered miRNA profiles in postmortem prefrontal cortex from schizophrenia patients.
Perkins
Diana O
DO
Department of Psychiatry, University of North Carolina at Chapel Hill, CB 7160, Chapel Hill, NC 27599, USA. diana_perkins@med.unc.edu
Jeffries
Clark D
CD
Jarskog
L Fredrik
LF
Thomson
J Michael
JM
Woods
Keith
K
Newman
Martin A
MA
Parker
Joel S
JS
Jin
Jianping
J
Hammond
Scott M
SM
D020816:Amino Acid Motifs / Q000235:genetics; D017931:DNA Primers; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D046228:Microarray Analysis; D017397:Prefrontal Cortex / Q000378:metabolism*; D011618:Psychotic Disorders / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012559:Schizophrenia / Q000235:genetics* / Q000378:metabolism
D017931:DNA Primers; D035683:MicroRNAs