BRCA1 alterations are associated with endometriosis, but BRCA2 alterations show no detectable endometriosis risk: a study in Indian population.
OBJECTIVE
To investigate the role of genetic variations and expression alterations of BRCA1 and BRCA2 genes in the pathophysiology of endometriosis.


METHODS
A genetic association study was conducted in 573 endometriosis cases and 490 controls of Indian origin. We genotyped 13 selected promoter SNPs of BRCA1 gene and 2 selected promoter SNPs of BRCA2 gene by PCR-sequencing analysis. In addition, to better understand genetic contributions to the pathophysiology of endometriosis, the expression pattern of BRCA1 & 2 was analyzed in the eutopic endometria of endometriosis cases and controls by western-blot and immunohistochemical analysis.


RESULTS
Our results revealed significant association between BRCA1 rs71361504 (-/GTT) SNP and endometriosis risk in Indian women (P < 0.0001), while the remaining SNPs of both BRCA1 & 2 genes showed no difference between cases and controls. Western-blot and immunohistochemical analysis revealed significantly decreased BRCA1 expression levels in eutopic endometria of patients compared with controls (P < 0.05). Furthermore, nuclear BRCA1 was frequently lost compared with cytoplasmic BRCA1 in eutopic endometria of patients. Expression of BRCA2 did not differ between patients and controls.


CONCLUSIONS
BRCA1 rs71361504 SNP may modify the endometriosis risk in Indian women. In addition, decreased expression of BRCA1 may play an important role in the pathophysiology of endometriosis. The analysis of BRCA1 genetic variants and/or expression might help to identify patients at high risk for disease outcome.
Department of Biochemistry, Osmania University, Hyderabad, 500 007, India.
Suresh
S
Govatati
Kiran
K
Challa
Sunita B
SB
Reddy
Kayathi
K
Pramod
Mamata
M
Deenadayal
Baidyanath
B
Chakravarty
Sisinthy
S
Shivaji
Manjula
M
Bhanoori
D000328:Adult; D019313:BRCA1 Protein / Q000235:genetics*; D024682:BRCA2 Protein / Q000235:genetics*; D016022:Case-Control Studies; D004715:Endometriosis / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007194:India; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D044465:White People / Q000235:genetics; D055815:Young Adult
D019313:BRCA1 Protein; C492913:BRCA1 protein, human; D024682:BRCA2 Protein; C551750:BRCA2 protein, human