The phospholipase C-gamma1 gene (PLCG1) and lithium-responsive bipolar disorder: re-examination of an intronic dinucleotide repeat polymorphism.
Twin, family and adoption studies have indicated that genetic susceptibility plays an important role in the etiology of bipolar disorder. Turecki et al. (1998) recently published preliminary evidence suggesting that bipolar patients with an excellent response to lithium treatment have a higher frequency of a specific dinucleotide repeat allele in the phospholipase Cgamma-1 (PLCG1) genomic region. The present work was undertaken to re-examine the finding by Turecki et al. in a sample of Norwegian lithium-treated bipolar patients sub-classified as lithium responders, non-responders, or partial responders/unclassified. The overall distribution of the PLCG1 dinucleotide repeat alleles was not significantly different between different categories of subjects. When analyzed according to presence or absence of different dinucleotide alleles, a PLCG1-8 repeat was more frequent among lithium responders vs controls. In line with Turecki et al., we also noticed a moderately over-representation of the PLCG1-5 repeat among the bipolar patients as compared to the controls.
Løvlie
R
R
Dr Einar Martens Research Group for Biological Psychiatry, Center for Medical Genetics and Molecular Medicine, University of Bergen, Haukeland University Hospital, Norway. rlov@haukeland.no
Berle
J O
JO
Stordal
E
E
Steen
V M
VM
D001714:Bipolar Disorder / Q000188:drug therapy* / Q000235:genetics*; D017931:DNA Primers; D018900:Dinucleotide Repeats; D020022:Genetic Predisposition to Disease; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D008094:Lithium / Q000627:therapeutic use*; D009664:Norway; D051966:Phospholipase C gamma; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D010738:Type C Phospholipases / Q000235:genetics*; D044465:White People
D017931:DNA Primers; D007527:Isoenzymes; D008094:Lithium; D010738:Type C Phospholipases; D051966:Phospholipase C gamma