Flora Lotte "Lola" Reiss outdoors in a garden Portraits Women

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Flora Lotte "Lola" Reiss driving a car Portraits Women

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Flora Lotte "Lola" Reiss outdoors in a garden Portraits Women

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Functional evaluation of genetic variants associated with endometriosis near GREB1

STUDY QUESTION: Do DNA variants in the growth regulation by estrogen in breast cancer 1 (GREB1) region regulate endometrial GREB1 expression and increase the risk of developing endometriosis in women? SUMMARY ANSWER: We identified new single nucleotide polymorphisms (SNPs) with strong association with endometriosis at the GREB1 locus although we did not detect altered GREB1 expression in endometriosis patients with defined genotypes. WHAT IS ALREADY KNOWN: Genome-wide association studies have identified the GREB1 region on chromosome 2p25.1 for increasing endometriosis risk. The differential expression of GREB1 has also been reported by others in association with endometriosis disease phenotype. STUDY DESIGN, SIZE, DURATION: Fine mapping studies comprehensively evaluated SNPs within the GREB1 region in a large-scale data set (>2500 cases and >4000 controls). Publicly available bioinformatics tools were employed to functionally annotate SNPs showing the strongest association signal with endometriosis risk. Endometrial GREB1 mRNA and protein expression was studied with respect to phases of the menstrual cycle (n = 2-45 per cycle stage) and expression quantitative trait loci (eQTL) analysis for significant SNPs were undertaken for GREB1 [mRNA (n = 94) and protein (n = 44) in endometrium]. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants in this study are females who provided blood and/or endometrial tissue samples in a hospital setting. The key SNPs were genotyped using Sequenom MassARRAY. The functional roles and regulatory annotations for identified SNPs are predicted by various publicly available bioinformatics tools. Endometrial GREB1 expression work employed qRT-PCR, western blotting and immunohistochemistry studies. MAIN RESULTS AND THE ROLE OF CHANCE: Fine mapping results identified a number of SNPs showing stronger association (0.004 < P < 0.032) with endometriosis risk than the original GWAS SNP (rs13394619) (P = 0.034). Some of these SNPs were predicted to have functional roles, for example, interaction with transcription factor motifs. The haplotype (a combination of alleles) formed by the risk alleles from two common SNPs showed significant association (P = 0.026) with endometriosis and epistasis analysis showed no evidence for interaction between the two SNPs, suggesting an additive effect of SNPs on endometriosis risk. In normal human endometrium, GREB1 protein expression was altered depending on the cycle stage (significantly different in late proliferative versus late secretory, P < 0.05) and cell type (glandular epithelium, not stromal cells). However, GREB1 expression in endometriosis cases versus controls and eQTL analyses did not reveal any significant changes. LIMITATIONS, REASONS FOR CAUTION: In silico prediction tools are generally based on cell lines different to our tissue and disease of interest. Functional annotations drawn from these analyses should be considered with this limitation in mind. We identified cell-specific and hormone-specific changes in GREB1 protein expression. The lack of a significant difference observed following our GREB1 expression studies may be the result of moderate power on mixed cell populations in the endometrial tissue samples. WIDER IMPLICATIONS OF THE FINDINGS: This study further implicates the GREB1 region on chromosome 2p25.1 and the GREB1 gene with involvement in endometriosis risk. More detailed functional studies are required to determine the role of the novel GREB1 transcripts in endometriosis pathophysiology. STUDY FUNDING/COMPETING INTERESTS: Funding for this work was provided by NHMRC Project Grants APP1012245, APP1026033, APP1049472 and APP1046880. There are no competing interests.

Ruth Augusta Beatrice Goldschmidt outside the Richmond Park Hotel; Karlsbad Portraits Women

Born 1923?

Ruth Augusta Beatrice Goldschmidt skiing; Italy Portraits Women

Born 1923?

Portrait of Ruth Augusta Beatrice Goldschmidt Portraits Women

Born 1923?

Studio portrait of Paula Goldschmidt née Harmelin; Leipzig Portraits Women

Born 1880?

Studio portrait of Paula Goldschmidt née Harmelin Portraits Women

Born 1880?

Dorothea (Dola) Guttmann outside the Zur Stelliner Dampfbaeckerei building Portraits Women

Born April 27, 1922 in Tilsit, died June 8, 2003 Zurich

Dorothea (Dola) Guttmann and two friends riding bicycles; Montreal Portraits Groups Women

Born April 27, 1922 in Tilsit, died June 8, 2003 Zurich

Studio portrait of Dorothea (Dola) Guttmann Portraits Women

Handwritten dedication on verso: To my very dear aunt and uncle, with love Dola Oct. '45

Dorothea (Dola) Guttmann learning to drive; Montreal Portraits Women

Born April 27, 1922 in Tilsit, died June 8, 2003 Zurich

Dorothea (Dola) Guttmann working at the International Rug Co. Ltd.; Montreal Portraits Women

Born April 27, 1922 in Tilsit, died June 8, 2003 Zurich

Dorothea (Dola) Guttmann Gould; Jerusalem Portraits Women

Born April 27, 1922 in Tilsit, died June 8, 2003 Zurich; Married to Henry H. Goldschmidt Gould August 7, 1960 in Montreal