Neuregulin 1 (NRG1 ) and schizophrenia: analysis of a US family sample and the evidence in the balance.
BACKGROUND
Individual genome-wide linkage scans and meta-analyses support that one or more susceptibility genes for schizophrenia are located in chromosome 8p. A gene from this region, neuregulin 1 (NRG1 ), known to be involved with glutamatergic function, has been found to be associated in some studied samples.


METHODS
We have examined a new combined schizophrenia sample with 136 schizophrenia families largely of European ancestry (EA) and 646 subjects with DNA. We genotyped 14 single nucleotide polymorphisms (SNPs) in NRG1 including those reported to comprise schizophrenia-associated haplotypes in Icelandic, Scottish, Irish, and Chinese Han populations.


RESULTS
We found no evidence of association at a single-marker or a haplotypic level. We review methodological aspects of previous studies to enable us to put our findings into context.


CONCLUSIONS
Our failure to find an association between NRG1 and schizophrenia might reflect different linkage disequilibrium (LD) patterns found in different populations, disease allelic heterogeneity, clinical heterogeneity of schizophrenia, or inadequate statistical power deriving from moderate sample size. NRG1, if a true gene for schizophrenia, accounts for a small fraction of the disease in most populations. The confirmation of NRG1 as a schizophrenia susceptibility gene will require studies with a comprehensive set of markers and in larger samples. The possibility remains that reports of NRG1 association might reflect false positives.
Duan
Jubao
J
Center for Psychiatric Genetics, Department of Psychiatry and Behavioral Sciences, Evanston Northwestern Healthcare Research Institute, and Northwestern University, 1001 University Place, Evanston, IL 60201, USA.
Martinez
Maria
M
Sanders
Alan R
AR
Hou
Cuiping
C
Krasner
Aaron J
AJ
Schwartz
Daniel B
DB
Gejman
Pablo V
PV
D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D005190:Family; D005260:Female; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D020890:Neuregulin-1; D012559:Schizophrenia / Q000235:genetics*; D014481:United States / Q000453:epidemiology; D044465:White People
D020890:Neuregulin-1