Chromosome contacts in activated T cells identify autoimmune disease candidate genes
GENOME BIOLOGY
Authors: Burren, Oliver S.; Garcia, Arcadio Rubio; Javierre, Biola-Maria; Rainbow, Daniel B.; Cairns, Jonathan; Cooper, Nicholas J.; Lambourne, John J.; Schofield, Ellen; Dopico, Xaquin Castro; Ferreira, Ricardo C.; Coulson, Richard; Burden, Frances; Rowlston, Sophia P.; Downes, Kate; Wingett, Steven W.; Frontini, Mattia; Ouwehand, Willem H.; Fraser, Peter; Spivakov, Mikhail; Todd, John A.; Wicker, Linda S.; Cutler, Antony J.; Wallace, Chris
Abstract
Background: Autoimmune disease-associated variants are preferentially found in regulatory regions in immune cells, particularly CD4(+) T cells. Linking such regulatory regions to gene promoters in disease-relevant cell contexts facilitates identification of candidate disease genes. Results: Within 4 h, activation of CD4(+) T cells invokes changes in histone modifications and enhancer RNA transcription that correspond to altered expression of the interacting genes identified by promoter capture Hi-C. By integrating promoter capture Hi-C data with genetic associations for five autoimmune diseases, we prioritised 245 candidate genes with a median distance from peak signal to prioritised gene of 153 kb. Just under half (108/245) prioritised genes related to activation-sensitive interactions. This included IL2RA, where allele-specific expression analyses were consistent with its interaction-mediated regulation, illustrating the utility of the approach. Conclusions: Our systematic experimental framework offers an alternative approach to candidate causal gene identification for variants with cell state-specific functional effects, with achievable sample sizes.
Genetic variants in interleukin genes are associated with breast cancer risk and survival in a genetically admixed population: the Breast Cancer Health Disparities Study
CARCINOGENESIS
Authors: Slattery, Martha L.; Herrick, Jennifer S.; Torres-Mejia, Gabriella; John, Esther M.; Giuliano, Anna R.; Hines, Lisa M.; Stern, Mariana C.; Baumgartner, Kathy B.; Presson, Angela P.; Wolff, Roger K.
Abstract
Interleukins (ILs) are key regulators of immune response. Genetic variation in IL genes may influence breast cancer risk and mortality given their role in cell growth, angiogenesis and regulation of inflammatory process. We examined 16 IL genes with breast cancer risk and mortality in an admixed population of Hispanic/Native American (NA) (2111 cases and 2597 controls) and non-Hispanic white (NHW) (1481 cases and 1585 controls) women. Adaptive Rank Truncated Product (ARTP) analysis was conducted to determine gene significance and lasso (least absolute shrinkage and selection operator) was used to identify potential gene by gene and gene by lifestyle interactions. The pathway was statistically significant for breast cancer risk overall (P-ARTP = 0.0006), for women with low NA ancestry (P-ARTP = 0.01), for premenopausal women (P-ARTP = 0.02), for estrogen receptor (ER)+/progesterone receptor (PR)+ tumors (P-ARTP = 0.03) and ER-/PR-tumors (P-ARTP = 0.02). Eight of the 16 genes evaluated were associated with breast cancer risk (IL1A, IL1B, IL1RN, IL2, IL2RA, IL4, IL6 and IL10); four genes were associated with breast cancer risk among women with low NA ancestry (IL1B, IL6, IL6R and IL10), two were associated with breast cancer risk among women with high NA ancestry (IL2 and IL2RA) and four genes were associated with premenopausal breast cancer risk (IL1A, IL1B, IL2 and IL3). IL4, IL6R, IL8 and IL17A were associated with breast cancer-specific mortality. We confirmed associations with several functional polymorphisms previously associated with breast cancer risk and provide support that their combined effect influences the carcinogenic process.