Association between common germline genetic variation in 94 candidate genes or regions and risks of invasive epithelial ovarian cancer.
BACKGROUND
Recent studies have identified several single nucleotide polymorphisms (SNPs) in the population that are associated with variations in the risks of many different diseases including cancers such as breast, prostate and colorectal. For ovarian cancer, the known highly penetrant susceptibility genes (BRCA1 and BRCA2) are probably responsible for only 40% of the excess familial ovarian cancer risks, suggesting that other susceptibility genes of lower penetrance exist.


METHODS
We have taken a candidate approach to identifying moderate risk susceptibility alleles for ovarian cancer. To date, we have genotyped 340 SNPs from 94 candidate genes or regions, in up to 1,491 invasive epithelial ovarian cancer cases and 3,145 unaffected controls from three different population based studies from the UK, Denmark and USA.


RESULTS
After adjusting for population stratification by genomic control, 18 SNPs (5.3%) were significant at the 5% level, and 5 SNPs (1.5%) were significant at the 1% level. The most significant association was for the SNP rs2107425, located on chromosome 11p15.5, which has previously been identified as a susceptibility allele for breast cancer from a genome wide association study (P-trend = 0.0012). When SNPs/genes were stratified into 7 different pathways or groups of validation SNPs, the breast cancer associated SNPs were the only group of SNPs that were significantly associated with ovarian cancer risk (P-heterogeneity = 0.0003; P-trend = 0.0028; adjusted (for population stratification) P-trend = 0.006). We did not find statistically significant associations when the combined data for all SNPs were analysed using an admixture maximum likelihood (AML) experiment-wise test for association (P-heterogeneity = 0.051; P-trend = 0.068).


CONCLUSIONS
These data suggest that a proportion of the SNPs we evaluated were associated with ovarian cancer risk, but that the effect sizes were too small to detect associations with individual SNPs.
Quaye
Lydia
L
Gynaecological Cancer Research Laboratories, UCL EGA Institute for Women's Health, University College London, London, United Kingdom.
Tyrer
Jonathan
J
Ramus
Susan J
SJ
Song
Honglin
H
Wozniak
Eva
E
DiCioccio
Richard A
RA
McGuire
Valerie
V
Høgdall
Estrid
E
Høgdall
Claus
C
Blaakaer
Jan
J
Goode
Ellen L
EL
Schildkraut
Joellen M
JM
Easton
Douglas F
DF
Krüger-Kjaer
Susanne
S
Whittemore
Alice S
AS
Gayther
Simon A
SA
Pharoah
Paul D P
PD
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010051:Ovarian Neoplasms / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012306:Risk