CAG repeats of CTG18.1 and KCNN3 in Korean patients with bipolar affective disorder.
BACKGROUND
Trinucleotide repetition combined with variable penetrance of expression could be responsible for the complex transmission pattern observed in bipolar affective disorder (BPAD). The purpose of this study was to investigate the association of excess longer allele of KCNN3 and CTG18.1 in the patients with BPAD.


METHODS
CAG/CTG repeat distribution in KCNN3, CTG 18.1 and ERDA1 was examined and the copy number of ligation product in repeat expansion detection (RED) was measured in Korean bipolar patients in comparison to ethnically matched healthy controls.


RESULTS
No significant difference was found in the allele distribution of those repeats between bipolar patients and controls. Ligation product size in RED was not increased in bipolar patients. However, the copy number of ligation product in RED was highly correlated with CAG/CTG copies of ERDA1 (P=0.0001), partly with CTG 18.1 (P=0.04), but not with KCNN3.


CONCLUSIONS
A longer CAG repeat alleles of KCNN3 or CTG 18.1 may not be a risk factor for BPAD in Korean population and the copy number of ligation product in RED in the patients with BPAD is influenced by the longer allele of CAG/CTG of ERDA1 or CTG 18.1.
Jin
D K
DK
Department of Pediatrics, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Ku, Seoul 135-710, South Korea.
Hwang
H Z
HZ
Oh
M R
MR
Kim
J S
JS
Lee
M
M
Kim
S
S
Lim
S W
SW
Seo
M Y
MY
Kim
J H
JH
Kim
D K
DK
D000328:Adult; D000483:Alleles; D001714:Bipolar Disorder / Q000145:classification / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005828:Genetics, Population; D005838:Genotype; D006801:Humans; D007723:Korea; D008297:Male; D015221:Potassium Channels / Q000235:genetics*; D024681:Potassium Channels, Calcium-Activated; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D051640:Small-Conductance Calcium-Activated Potassium Channels; D019680:Trinucleotide Repeat Expansion; D018911:Trinucleotide Repeats
C406328:KCNN3 protein, human; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D051640:Small-Conductance Calcium-Activated Potassium Channels