@article{IslesIngasonLowtheretal.2016,
  author    = {Isles, Anthony R. and Ingason, Andr{\´e}s and Lowther, Chelsea and Walters, James and Gawlick, Micha and St{\"o}ber, Gerald and Rees, Elliott and Martin, Joanna and Little, Rosie B. and Potter, Harry and Georgieva, Lyudmila and Pizzo, Lucilla and Ozaki, Norio and Aleksic, Branko and Kushima, Itaru and Ikeda, Masashi and Iwata, Nakao and Levinson, Douglas F. and Gejman, Pablo V. and Shi, Jianxin and Sanders, Alan R. and Duan, Jubao and Willis, Joseph and Sisodiya, Sanjay and Costain, Gregory and Werge, Thomas M. and Degenhardt, Franziska and Giegling, Ina and Rujescu, Dan and Hreidarsson, Stefan J. and Saemundsen, Evald and Ahn, Joo Wook and Ogilvie, Caroline and Girirajan, Santhosh D. and Stefansson, Hreinn and Stefansson, Kari and O'Donovan, Michael C. and Owen, Michael J. and Bassett, Anne and Kirov, George},
  title     = {Parental Origin of Interstitial Duplications at 15q11.2-q13.3 in Schizophrenia and Neurodevelopmental Disorders},
  series = {PLoS Genetics},
  volume    = {12},
  journal   = {PLoS Genetics},
  number    = {5},
  doi       = {10.1371/journal.pgen.1005993},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166706},
  pages     = {e1005993},
  year      = {2016},
  abstract  = {Duplications at 15q11.2-q13.3 overlapping the Prader-Willi/Angelman syndrome (PWS/AS) region have been associated with developmental delay (DD), autism spectrum disorder (ASD) and schizophrenia (SZ). Due to presence of imprinted genes within the region, the parental origin of these duplications may be key to the pathogenicity. Duplications of maternal origin are associated with disease, whereas the pathogenicity of paternal ones is unclear. To clarify the role of maternal and paternal duplications, we conducted the largest and most detailed study to date of parental origin of 15q11.2-q13.3 interstitial duplications in DD, ASD and SZ cohorts. We show, for the first time, that paternal duplications lead to an increased risk of developing DD/ASD/multiple congenital anomalies (MCA), but do not appear to increase risk for SZ. The importance of the epigenetic status of 15q11.2-q13.3 duplications was further underlined by analysis of a number of families, in which the duplication was paternally derived in the mother, who was unaffected, whereas her offspring, who inherited a maternally derived duplication, suffered from psychotic illness. Interestingly, the most consistent clinical characteristics of SZ patients with 15q11.2-q13.3 duplications were learning or developmental problems, found in 76\% of carriers. Despite their lower pathogenicity, paternal duplications are less frequent in the general population with a general population prevalence of 0.0033\% compared to 0.0069\% for maternal duplications. This may be due to lower fecundity of male carriers and differential survival of embryos, something echoed in the findings that both types of duplications are de novo in just over 50\% of cases. Isodicentric chromosome 15 (idic15) or interstitial triplications were not observed in SZ patients or in controls. Overall, this study refines the distinct roles of maternal and paternal interstitial duplications at 15q11.2-q13.3, underlining the critical importance of maternally expressed imprinted genes in the contribution of Copy Number Variants (CNVs) at this interval to the incidence of psychotic illness. This work will have tangible benefits for patients with 15q11.2-q13.3 duplications by aiding genetic counseling.},
  language  = {en}
}
@article{HavikDegenhardtJohanssonetal.2012,
  author    = {Havik, Bjarte and Degenhardt, Franziska A. and Johansson, Stefan and Fernandes, Carla P. D. and Hinney, Anke and Scherag, Andr{\´e} and Lybaek, Helle and Djurovic, Srdjan and Christoforou, Andrea and Ersland, Kari M. and Giddaluru, Sudheer and O'Donovan, Michael C. and Owen, Michael J. and Craddock, Nick and M{\"u}hleisen, Thomas W. and Mattheisen, Manuel and Schimmelmann, Benno G. and Renner, Tobias and Warnke, Andreas and Herpertz-Dahlmann, Beate and Sinzig, Judith and Albayrak, {\"O}zg{\"u}r and Rietschel, Marcella and N{\"o}then, Markus M. and Bramham, Clive R. and Werge, Thomas and Hebebrand, Johannes and Haavik, Jan and Andreassen, Ole A. and Cichon, Sven and Steen, Vidar M. and Le Hellard, Stephanie},
  title     = {DCLK1 Variants Are Associated across Schizophrenia and Attention Deficit/Hyperactivity Disorder},
  series = {PLoS One},
  volume    = {7},
  journal   = {PLoS One},
  number    = {4},
  doi       = {10.1371/journal.pone.0035424},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135285},
  pages     = {e35424},
  year      = {2012},
  abstract  = {Doublecortin and calmodulin like kinase 1 (DCLK1) is implicated in synaptic plasticity and neurodevelopment. Genetic variants in DCLK1 are associated with cognitive traits, specifically verbal memory and general cognition. We investigated the role of DCLK1 variants in three psychiatric disorders that have neuro-cognitive dysfunctions: schizophrenia (SCZ), bipolar affective disorder (BP) and attention deficit/hyperactivity disorder (ADHD). We mined six genome wide association studies (GWASs) that were available publically or through collaboration; three for BP, two for SCZ and one for ADHD. We also genotyped the DCLK1 region in additional samples of cases with SCZ, BP or ADHD and controls that had not been whole-genome typed. In total, 9895 subjects were analysed, including 5308 normal controls and 4,587 patients (1,125 with SCZ, 2,496 with BP and 966 with ADHD). Several DCLK1 variants were associated with disease phenotypes in the different samples. The main effect was observed for rs7989807 in intron 3, which was strongly associated with SCZ alone and even more so when cases with SCZ and ADHD were combined (P-value = 4x10\(^{-5}\) and 4x10\(^{-6}\), respectively). Associations were also observed with additional markers in intron 3 (combination of SCZ, ADHD and BP), intron 19 (SCZ+BP) and the 3'UTR (SCZ+BP). Our results suggest that genetic variants in DCLK1 are associated with SCZ and, to a lesser extent, with ADHD and BP. Interestingly the association is strongest when SCZ and ADHD are considered together, suggesting common genetic susceptibility. Given that DCLK1 variants were previously found to be associated with cognitive traits, these results are consistent with the role of DCLK1 in neurodevelopment and synaptic plasticity.},
  language  = {en}
}