• At-risk variant in TCF7L2 for type II diabetes increases risk of schizophrenia.

      Hansen, Thomas; Ingason, Andrés; Djurovic, Srdjan; Melle, Ingrid; Fenger, Mogens; Gustafsson, Omar; Jakobsen, Klaus D; Rasmussen, Henrik B; Tosato, Sarah; Rietschel, Marcella; et al. (Elsevier, 2011-07-01)
      BACKGROUND: Schizophrenia is associated with increased risk of type II diabetes and metabolic disorders. However, it is unclear whether this comorbidity reflects shared genetic risk factors, at-risk lifestyle, or side effects of antipsychotic medication. METHODS: Eleven known risk variants of type II diabetes were genotyped in patients with schizophrenia in a sample of 410 Danish patients, each matched with two healthy control subjects on sex, birth year, and month. Replication was carried out in a large multinational European sample of 4089 patients with schizophrenia and 17,597 controls (SGENE+) using Mantel-Haenszel test. RESULTS: One type II diabetes at-risk allele located in TCF7L2, rs7903146 [T], was associated with schizophrenia in the discovery sample (p = .0052) and in the replication with an odds ratio of 1.07 (95% confidence interval 1.01-1.14, p = .033). CONCLUSION: The association reported here with a well-known diabetes variant suggests that the observed comorbidity is partially caused by genetic risk variants. This study also demonstrates how genetic studies can successfully examine an epidemiologically derived hypothesis of comorbidity.
    • Common variants at VRK2 and TCF4 conferring risk of schizophrenia.

      Steinberg, Stacy; de Jong, Simone; Andreassen, Ole A; Werge, Thomas; Børglum, Anders D; Mors, Ole; Mortensen, Preben B; Gustafsson, Omar; Costas, Javier; Pietiläinen, Olli P H; et al. (Oxford University Press, 2011-10-15)
      Common sequence variants have recently joined rare structural polymorphisms as genetic factors with strong evidence for association with schizophrenia. Here we extend our previous genome-wide association study and meta-analysis (totalling 7 946 cases and 19 036 controls) by examining an expanded set of variants using an enlarged follow-up sample (up to 10 260 cases and 23 500 controls). In addition to previously reported alleles in the major histocompatibility complex region, near neurogranin (NRGN) and in an intron of transcription factor 4 (TCF4), we find two novel variants showing genome-wide significant association: rs2312147[C], upstream of vaccinia-related kinase 2 (VRK2) [odds ratio (OR) = 1.09, P = 1.9 × 10(-9)] and rs4309482[A], between coiled-coiled domain containing 68 (CCDC68) and TCF4, about 400 kb from the previously described risk allele, but not accounted for by its association (OR = 1.09, P = 7.8 × 10(-9)).
    • Convergent lines of evidence support CAMKK2 as a schizophrenia susceptibility gene.

      Luo, X-J; Li, M; Huang, L; Steinberg, S; Mattheisen, M; Liang, G; Donohoe, G; Shi, Y; Chen, C; Yue, W; et al. (Nature Publishing Group, 2014-07)
      Genes that are differentially expressed between schizophrenia patients and healthy controls may have key roles in the pathogenesis of schizophrenia. We analyzed two large-scale genome-wide expression studies, which examined changes in gene expression in schizophrenia patients and their matched controls. We found calcium/calmodulin (CAM)-dependent protein kinase kinase 2 (CAMKK2) is significantly downregulated in individuals with schizophrenia in both studies. To seek the potential genetic variants that may regulate the expression of CAMKK2, we investigated the association between single-nucleotide polymorphisms (SNPs) within CAMKK2 and the expression level of CAMKK2. We found one SNP, rs1063843, which is located in intron 17 of CAMKK2, is strongly associated with the expression level of CAMKK2 in human brains (P=1.1 × 10(-6)) and lymphoblastoid cell lines (the lowest P=8.4 × 10(-6)). We further investigated the association between rs1063843 and schizophrenia in multiple independent populations (a total of 130 623 subjects) and found rs1063843 is significantly associated with schizophrenia (P=5.17 × 10(-5)). Interestingly, we found the T allele of rs1063843, which is associated with lower expression level of CAMKK2, has a higher frequency in individuals with schizophrenia in all of the tested samples, suggesting rs1063843 may be a causal variant. We also found that rs1063843 is associated with cognitive function and personality in humans. In addition, protein-protein interaction (PPI) analysis revealed that CAMKK2 participates in a highly interconnected PPI network formed by top schizophrenia genes, which further supports the potential role of CAMKK2 in the pathogenesis of schizophrenia. Taken together, these converging lines of evidence strongly suggest that CAMKK2 may have pivotal roles in schizophrenia susceptibility.
    • Identification of six new susceptibility loci for invasive epithelial ovarian cancer.

      Kuchenbaecker, Karoline B; Ramus, Susan J; Tyrer, Jonathan; Lee, Andrew; Shen, Howard C; Beesley, Jonathan; Lawrenson, Kate; McGuffog, Lesley; Healey, Sue; Lee, Janet M; et al. (Nature Publishing Group, 2015-02)
      Genome-wide association studies (GWAS) have identified 12 epithelial ovarian cancer (EOC) susceptibility alleles. The pattern of association at these loci is consistent in BRCA1 and BRCA2 mutation carriers who are at high risk of EOC. After imputation to 1000 Genomes Project data, we assessed associations of 11 million genetic variants with EOC risk from 15,437 cases unselected for family history and 30,845 controls and from 15,252 BRCA1 mutation carriers and 8,211 BRCA2 mutation carriers (3,096 with ovarian cancer), and we combined the results in a meta-analysis. This new study design yielded increased statistical power, leading to the discovery of six new EOC susceptibility loci. Variants at 1p36 (nearest gene, WNT4), 4q26 (SYNPO2), 9q34.2 (ABO) and 17q11.2 (ATAD5) were associated with EOC risk, and at 1p34.3 (RSPO1) and 6p22.1 (GPX6) variants were specifically associated with the serous EOC subtype, all with P < 5 × 10(-8). Incorporating these variants into risk assessment tools will improve clinical risk predictions for BRCA1 and BRCA2 mutation carriers.
    • Parental origin of sequence variants associated with complex diseases

      Kong, Augustine; Steinthorsdottir, Valgerdur; Masson, Gisli; Thorleifsson, Gudmar; Sulem, Patrick; Besenbacher, Soren; Jonasdottir, Aslaug; Sigurdsson, Asgeir; Kristinsson, Kari Th; Jonasdottir, Adalbjorg; et al. (Nature Publishing Group, 2009-12)
      Effects of susceptibility variants may depend on from which parent they are inherited. Although many associations between sequence variants and human traits have been discovered through genome-wide associations, the impact of parental origin has largely been ignored. Here we show that for 38,167 Icelanders genotyped using single nucleotide polymorphism (SNP) chips, the parental origin of most alleles can be determined. For this we used a combination of genealogy and long-range phasing. We then focused on SNPs that associate with diseases and are within 500 kilobases of known imprinted genes. Seven independent SNP associations were examined. Five-one with breast cancer, one with basal-cell carcinoma and three with type 2 diabetes-have parental-origin-specific associations. These variants are located in two genomic regions, 11p15 and 7q32, each harbouring a cluster of imprinted genes. Furthermore, we observed a novel association between the SNP rs2334499 at 11p15 and type 2 diabetes. Here the allele that confers risk when paternally inherited is protective when maternally transmitted. We identified a differentially methylated CTCF-binding site at 11p15 and demonstrated correlation of rs2334499 with decreased methylation of that site.
    • A sequence variant at 4p16.3 confers susceptibility to urinary bladder cancer

      Kiemeney, Lambertus A; Sulem, Patrick; Besenbacher, Soren; Vermeulen, Sita H; Sigurdsson, Asgeir; Thorleifsson, Gudmar; Gudbjartsson, Daniel F; Stacey, Simon N; Gudmundsson, Julius; Zanon, Carlo; et al. (Nature Pub. Co., 2010-05-01)
      Previously, we reported germline DNA variants associated with risk of urinary bladder cancer (UBC) in Dutch and Icelandic subjects. Here we expanded the Icelandic sample set and tested the top 20 markers from the combined analysis in several European case-control sample sets, with a total of 4,739 cases and 45,549 controls. The T allele of rs798766 on 4p16.3 was found to associate with UBC (odds ratio = 1.24, P = 9.9 x 10(-12)). rs798766 is located in an intron of TACC3, 70 kb from FGFR3, which often harbors activating somatic mutations in low-grade, noninvasive UBC. Notably, rs798766[T] shows stronger association with low-grade and low-stage UBC than with more aggressive forms of the disease and is associated with higher risk of recurrence in low-grade stage Ta tumors. The frequency of rs798766[T] is higher in Ta tumors that carry an activating mutation in FGFR3 than in Ta tumors with wild-type FGFR3. Our results show a link between germline variants, somatic mutations of FGFR3 and risk of UBC.
    • Targeting oncogenic serine/threonine-protein kinase BRAF in cancer cells inhibits angiogenesis and abrogates hypoxia.

      Bottos, Alessia; Martini, Miriam; Di Nicolantonio, Federica; Comunanza, Valentina; Maione, Federica; Minassi, Alberto; Appendino, Giovanni; Bussolino, Federico; Bardelli, Alberto; Inst Canc Res & Treatment, Lab Vasc Oncol, I-10060 Turin, Italy, Univ Torino, Dept Oncol Sci, I-10060 Turin, Italy, Inst Canc Res & Treatment, Lab Mol Genet, I-10060 Turin, Italy, Fdn Italiana Ric Cancro, Inst Mol Oncol, I-20139 Milan, Italy, Inst Canc Res & Treatment, Lab Transgen Mouse Models, I-10060 Turin, Italy, Univ Piemonte Orientale, Dipartimento Sci Chim Alimentari Farmaceut & Farm, I-28100 Novara, Italy (Natl Acad Sciences, 2012-02-07)
      Carcinomas are comprised of transformed epithelial cells that are supported in their growth by a dedicated neovasculature. How the genetic milieu of the epithelial compartment influences tumor angiogenesis is largely unexplored. Drugs targeted to mutant cancer genes may act not only on tumor cells but also, directly or indirectly, on the surrounding stroma. We investigated the role of the BRAF(V600E) oncogene in tumor/vessel crosstalk and analyzed the effect of the BRAF inhibitor PLX4720 on tumor angiogenesis. Knock-in of the BRAF(V600E) allele into the genome of human epithelial cells triggered their angiogenic response. In cancer cells harboring oncogenic BRAF, the inhibitor PLX4720 switches off the ERK pathway and inhibits the expression of proangiogenic molecules. In tumor xenografts harboring the BRAF(V600E), PLX4720 extensively modifies the vascular network causing abrogation of hypoxia. Overall, our results provide a functional link between oncogenic BRAF and angiogenesis. Furthermore, they indicate how the tumor vasculature can be "indirectly" besieged through targeting of a genetic lesion to which the cancer cells are addicted.