Habituation in prepulse inhibition is affected by a polymorphism on the NMDA receptor 2B subunit gene (GRIN2B).
OBJECTIVE
To identify the reliable connectivity between causal genes or variants with an abnormality expressed in a certain endophenotype has been viewed as a crucial step in unraveling the etiology of schizophrenia because of the considerable heterogeneity in this disorder.


METHODS
According to this practical and scientific demand, we aimed to investigate the relationship between seven top-ranked variants in the SZgene database [120-bpTR in DRD4, rs1801028 and rs6277 in DRD2, rs1019385 (T200G) in GRIN2B, rs1800532 in TPH1, rs1801133 (C677T) in MTHFR, rs2619528 (P1765) in DTNBP1] and prepulse inhibition (PPI) and habituation after acoustic stimulus (HAB).


RESULTS
Both PPI and HAB were decreased significantly in patients with schizophrenia. In addition, we observed a significant effect of GRIN2B (human NMDA receptor 2B subunit gene, NR2B) genotype on HAB (P<0.05, not corrected).


CONCLUSIONS
Although these findings need to be replicated in other samples, an underlying mechanism of impaired biological reaction may be influenced by NMDA hypofunctioning in schizophrenia.
Hokyo
Akira
A
Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka, Japan.
Kanazawa
Tetsufumi
T
Uenishi
Hiroyuki
H
Tsutsumi
Atsushi
A
Kawashige
Seiya
S
Kikuyama
Hiroki
H
Glatt
Stephen J
SJ
Koh
Jun
J
Nishimoto
Yoshiyuki
Y
Matsumura
Hitoshi
H
Motomura
Naoyasu
N
Yoneda
Hiroshi
H
D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics*; D012559:Schizophrenia / Q000235:genetics / Q000503:physiopathology*
C121001:NR2B NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate