Stephanie Francoise Claire Le Hellard
Position
Professor, Human Genetics
Affiliation
Research
The aim of my research group is to identify how different layers of genetics, epigenetics and gene expression can be involved together in the development of mental disorders, their outcome and how they are modulated by the environment.
I am a core researcher at the NORMENT, a Norwegian Centre of Excellence for Research on Mental Health. The NORMENT is described here: http://www.med.uio.no/norment/english/ In Bergen I am situated at the Dr Martens group for research on biological psychiatry, our research activity is described here: http://www.uib.no/en/rg/geneticsgroup/106397/martens-group#at-a-glance
Description of our group in the NORMENT centre:
Epigenetics of Mental Disorders
About the groupThe group consists of people with background in genetics, statistics, medicine and informatics who together bring their complementary expertise to try understand the interaction between genetic and environmental risk in mental disorders. We work in close collaboration with clinicians.
We use datasets generated in house or publicly available that combine genetic, epigenetic and gene expression datasets for mental disorders (mostly schizophrenia and bipolar disorders) that are in addition well annotated for environmental factors.
AimsTogether with the members of my group we are focusing our research on the Epigenetics of Mental Disorders and their treatment (incl. treatment response).
Most of mental disorders are multifactorial in nature, which means that several genetic risk factors combined with environmental risk factors increase the risk to develop a disorder.
Epigenetic modifications, are changes added to the DNA (without changing the DNA sequence) that can regulate the expression of genes, for example the addition of methylation groups on the DNA (aka DNA methylation). Some of these modifications can be dependent of the genetic background, on the biological development (age or sex) or influenced by the environment (e.g. risk factors or treatment). We are especially interested in DNA methylation differences between patients with mental disorders such as schizophrenia, bipolar disorder, anxiety, OCD... and controls. DNA methylation differences are also observed under exposure to some environmental factors such as smoking, stress, cannabis use, etc... There are also some studies that have reported how treatment with either antidepressant or with cognitive therapy can be associated with differences in DNA methylation.
Thus the aim of our research is to identify epigenetic factors associated with the different aspects of psychiatric disorders: the risk to develop such disorders and how to treat them.
Specifically our projects are aimed at:
- Investigating epigenetic modifications in schizophrenia, bipolar disorder and anxiety disorders.
- Molecular mechanisms of exposure to several environmental risk in patients with psychosis (cannabis, trauma, asphyxia, ...).
- Identification of regions of differential methylation across psychiatric disorders and through the life span.
- DNA methylation changes associated with treatment and treatment response in OCD, psychosis and depression.
The group currently consist of 1 senior researcher, 2 postdocs, 3 PhD students, 1 forskerlinje student, 1 bio-engineer and myself.
Teaching
I teach Genetics and Evolution to medical students in their 3rd semester, at the Faculty of Medicine, UiB.
I teach a MSc course in Human Genetics (HUMGEN301) at the Faculty of Medicine, UiB. https://www.uib.no/en/course/HUMGEN301
I also participate in the IGSIN course for PhD students, UiB, and the Master course in Genetics of Cognitive Neuroscience at the University of Oslo.
Publications
Academic article
- Løkhammer, Solveig Brunstad; Koller, Dora; Wendt, Frank R. et al. (2024). Distinguishing vulnerability and resilience to posttraumatic stress disorder evaluating traumatic experiences, genetic risk and electronic health records. (external link)
- Tesfaye, Markos ; Spindola, Leticia Maria Nery; Stavrum, Anne-Kristin Støbakk et al. (2024). Sex effects on DNA methylation affect discovery in epigenome-wide association study of schizophrenia. (external link)
- Chrétienneau, Clara; Spindola, Leticia Maria Nery; Vorspan, Florence et al. (2024). An epigenetic candidate–gene association study of parental styles in suicide attempters with substance use disorders. (external link)
- Bakke, Laura Anne Wortinger; Stavrum, Anne-Kristin Støbakk; Shadrin, Alexey et al. (2024). Divergent epigenetic responses to perinatal asphyxia in severe mental disorders. (external link)
- Hagen, Kristen; Solem, Stian; Stavrum, Anne-Kristin Støbakk et al. (2023). Changes in mental health symptoms from April (COVID-19 outbreak) to December 2020 in Norway: A two-wave study. (external link)
- Villar, Jonelle Marie Dickow; Stavrum, Anne-Kristin Støbakk; Nery Spindola, Leticia Maria et al. (2023). Differences in white blood cell proportions between schizophrenia cases and controls are influenced by medication and variations in time of day. (external link)
- Bøen, Rune; Kaufmann, Tobias Herbert; van der Meer, Dennis et al. (2023). Beyond the Global Brain Differences: Intraindividual Variability Differences in 1q21.1 Distal and 15q11.2 BP1-BP2 Deletion Carriers. (external link)
- Frid, Leila Marie; Kessler, Ute; Ousdal, Olga Therese et al. (2023). Neurobiological mechanisms of ECT and TMS treatment in depression: study protocol of a multimodal magnetic resonance investigation. (external link)
- Grøtte, Torun; Hagen, Kristen; Eid, Jarle et al. (2022). Changes in contamination-related obsessions and compulsions during the COVID-19 pandemic: A Norwegian longitudinal study. (external link)
- Lassen, Espen Rasmussen; Hagen, Kristen; Kvale, Gerd et al. (2022). Personality traits and hardiness as risk- and protective factors for mental distress during the COVID-19 pandemic: a Norwegian two-wave study. (external link)
- Løkhammer, Solveig; Stavrum, Anne-Kristin Støbakk; Polushina, Tatiana et al. (2022). An epigenetic association analysis of childhood trauma in psychosis reveals possible overlap with methylation changes associated with PTSD. (external link)
- Brouwer, Rachel M.; Klein, Marieke; Grasby, Katrina L. et al. (2022). Genetic variants associated with longitudinal changes in brain structure across the lifespan. (external link)
- Sønderby, Ida Elken; van der Meer, Dennis; Moreau, Clara et al. (2021). 1q21.1 distal copy number variants are associated with cerebral and cognitive alterations in humans. (external link)
- Polushina, Tatiana; Banerjee, Niladri; Giddaluru, Sudheer et al. (2021). Identification of pleiotropy at the gene level between psychiatric disorders and related traits. (external link)
- Hagen, Kristen; Solem, Stian; Stavrum, Anne-Kristin Støbakk et al. (2021). Mental health symptoms during the first months of the COVID-19 outbreak in Norway: A cross-sectional survey study. (external link)
- Lam, Max; Chen, Chia-Yen; Ge, Tian et al. (2021). Identifying nootropic drug targets via large-scale cognitive GWAS and transcriptomics. (external link)
- Unnarsdóttir, Anna Bára; Lovik, Anikó; Fawns-Ritchie, Chloe et al. (2021). Cohort Profile: COVIDMENT: COVID-19 cohorts on mental health across six nations. (external link)
- Grasby, Katrina L.; Jahanshad, Neda; Painter, Jodie N et al. (2020). The genetic architecture of the human cerebral cortex. (external link)
- Bryois, Julien; Skene, Nathan G.; Hansen, Thomas Folkmann et al. (2020). Genetic identification of cell types underlying brain complex traits yields insights into the etiology of Parkinson’s disease. (external link)
- Elvsåshagen, Torbjørn; Bahrami, Shahram; van der Meer, Dennis et al. (2020). The genetic architecture of human brainstem structures and their involvement in common brain disorders. (external link)
- Munn-Chernoff, Melissa A.; Johnson, Emma C.; Chou, Yi-Ling et al. (2020). Shared genetic risk between eating disorder‐ and substance‐use‐related phenotypes: Evidence from genome‐wide association studies. (external link)
- Szabo, Attila; Akkouh, Ibrahim; Ueland, Thor et al. (2020). Cannabis Use Is Associated With Increased Levels of Soluble gp130 in Schizophrenia but Not in Bipolar Disorder. (external link)
- Còrdova Palomera, Aldo; van der Meer, Dennis; Kaufmann, Tobias et al. (2020). Genetic control of variability in subcortical and intracranial volumes. (external link)
- Satizabal, Claudia L.; Adams, Hieab H.H.; Hibar, Derrek et al. (2019). Genetic architecture of subcortical brain structures in 38,851 individuals. (external link)
- Lee, Phil H.; Antilla, Verneri; Won, Hyejung et al. (2019). Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders. (external link)
- Lam, Max; Hill, W. David; Trampush, Joey W. et al. (2019). Pleiotropic meta-analysis of cognition, education, and schizophrenia differentiates roles of early neurodevelopmental and adult synaptic pathways. (external link)
- Watson, Hunna J.; Yilmaz, Zeynep; Thornton, Laura M. et al. (2019). Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa. (external link)
- Kaufmann, Tobias; van der Meer, Dennis; Doan, Nhat Trung et al. (2019). Common brain disorders are associated with heritable patterns of apparent aging of the brain. (external link)
- van der Meer, Dennis; Sønderby, Ida Elken; Kaufmann, Tobias et al. (2019). Association of copy number variation of the 15q11.2 BP1-BP2 region with cortical and subcortical morphology and cognition. (external link)
- Stokowy, Tomasz; Polushina, Tatiana; Sønderby, Ida Elken et al. (2018). Genetic variation in 117 myelination-related genes in schizophrenia: Replication of association to lipid biosynthesis genes. (external link)
- Fan, Chun Chieh; Schork, Andrew J.; Brown, Timothy T. et al. (2018). Williams Syndrome neuroanatomical score associates with GTF2IRD1 in large-scale magnetic resonance imaging cohorts: A proof of concept for multivariate endophenotypes. (external link)
- Banerjee, Niladri; Polushina, Tatiana; Bettella, Francesco et al. (2018). Recently evolved human-specific methylated regions are enriched in schizophrenia signals. (external link)
- Davies, Gail; Lam, Max; Harris, Sarah E. et al. (2018). Study of 300,486 individuals identifies 148 independent genetic loci influencing general cognitive function. (external link)
- Savage, Jeanne E.; Jansen, Philip R.; Stringer, Sven et al. (2018). Genome-wide association meta-analysis in 269,867 individuals identifies new genetic and functional links to intelligence. (external link)
- van der Meer, Dennis; Rokicki, Jaroslav; Kaufmann, Tobias et al. (2018). Brain scans from 21,297 individuals reveal the genetic architecture of hippocampal subfield volumes. (external link)
- Hughes, Timothy; Sønderby, Ida Elken; Polushina, Tatiana et al. (2018). Elevated expression of a minor isoform of ANK3 is a risk factor for bipolar disorder. (external link)
- Banerjee, Niladri; Polushina, Tatiana; Bettella, Francesco et al. (2018). Analysis of differentially methylated regions in great apes and extinct hominids provides support for the evolutionary hypothesis of schizophrenia. (external link)
- Tronstad, Rune Rose; Polushina, Tatiana; Brattbakk, Hans-Richard et al. (2018). Genetic and transcriptional analysis of inflammatory bowel disease-associated pathways in patients with GUCY2C-linked familial diarrhea. (external link)
- Witoelar, Aree; Rongve, Arvid; Almdahl, Ina Selseth et al. (2018). Meta-analysis of Alzheimer’s disease on 9,751 samples from Norway and IGAP study identifies four risk loci. (external link)
- Lam, Max; Trampush, Joey W.; Yu, Jin et al. (2017). Large-scale cognitive GWAS meta-analysis reveals tissue-specific neural expression and potential nootropic drug targets. (external link)
- Polushina, Tatiana; Giddaluru, Sudheer; Bettella, Francesco et al. (2017). Analysis of the joint effect of SNPs to identify independent loci and allelic heterogeneity in schizophrenia GWAS data. (external link)
- Trampush, Joey W.; Yang, M.L.Z.; Yu, Jin et al. (2017). GWAS meta-analysis reveals novel loci and genetic correlates for general cognitive function: a report form the COGENT consortium. (external link)
- Li, Dong; Chang, Xiao; Connolly, John J. et al. (2017). A genome-wide association study of anorexia nervosa suggests a risk locus implicated in dysregulated leptin signaling. (external link)
- Jensen, Jacob Malte; Villesen, Palle; Friborg, Rune Møllegaard et al. (2017). Assembly and analysis of 100 full MHC haplotypes from the Danish population. (external link)
- Le Hellard, Stephanie; Wang, Yunpeng; Witoelar, Aree et al. (2017). Identification of gene loci that overlap between schizophrenia and educational attainment. (external link)
- Hibar, Derrek; Adams, Hieab H.H.; Jahanshad, Neda et al. (2017). Novel genetic loci associated with hippocampal volume. (external link)
- Aas, Monica; Melle, Ingrid; Bettella, Francesco et al. (2017). Psychotic patients who used cannabis frequently before illness onset have higher genetic predisposition to schizophrenia than those who did not. (external link)
- Maretty, Lasse; Jensen, Jacob Malte; Petersen, Bent et al. (2017). Sequencing and de novo assembly of 150 genomes from Denmark as a population reference. (external link)
- Athanasiu, Lavinia; Giddaluru, Sudheer; Neto, Carla Patricia Duarte Fernande et al. (2017). A genetic association study of CSMD1 and CSMD2 with cognitive function. (external link)
- Athanasiadis, Georgios; Cheng, Jade Y.; Vilhjálmsson, Bjarni J. et al. (2016). Nationwide genomic study in Denmark reveals remarkable population homogeneity. (external link)
- Thun, Eirunn; Le Hellard, Stephanie; Osland, Teresa Maria et al. (2016). Circadian clock gene variants and insomnia, sleepiness, and shift work disorder. (external link)
- Howrigan, Dave; Simonson, M.A.; Davies, Gail et al. (2016). Genome-wide autozygosity is associated with lower general cognitive ability. (external link)
- Giddaluru, Sudheer; Espeseth, Thomas; Salami, Alireza et al. (2016). Genetics of structural connectivity and information processing in the brain. (external link)
- Adams, Hieab H.H.; Hibar, Derrek; Chouraki, Vincent et al. (2016). Novel genetic loci underlying human intracranial volume identified through genome-wide association. (external link)
- Qian, Peng; Schork, Andrew J.; Bartsch, Hauke et al. (2016). Conservation of Distinct Genetically-Mediated Human Cortical Pattern. (external link)
- Steen, Vidar Martin; Skrede, Silje; Polushina, Tatiana et al. (2016). Genetic evidence for a role of the SREBP transcription system and lipid biosynthesis in schizophrenia and antipsychotic treatment. (external link)
- Trampush, Joey W.; Lencz, Todd; Knowles, Emma et al. (2015). Independent evidence for an association between general cognitive ability and a genetic locus for educational attainment. (external link)
- Hibar, Derrek; Stein, Jason L; Renteria, Miguel E et al. (2015). Common genetic variants influence human subcortical brain structures. (external link)
- Hansell, Narelle K.; Halford, Graeme S.; Andrews, Glenda et al. (2015). Genetic basis of a cognitive complexity metric. (external link)
- Davies, Gail; Armstrong, N; Bis, JC et al. (2015). Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53 949). (external link)
- Chen, Chi-Hua; Peng, Qian; Schork, Andrew J. et al. (2015). Large-scale genomics unveil polygenic architecture of human cortical surface area. (external link)
- Myrum, Craig; Giddaluru, Sudheer; Jacobsen, Kaya Kvarme et al. (2015). Common variants in the ARC gene are not associated with cognitive abilities. (external link)
- Duarte Fernandes, Carla; Westlye, Lars Tjelta; Giddaluru, Sudheer et al. (2014). Lack of association of the rs1344706 ZNF804A variant with cognitive functions and DTI indices of white matter microstructure in two independent healthy populations. (external link)
- Norheim, Katrine Brække; Le Hellard, Stephanie; Nordmark, Gunnel et al. (2014). A possible genetic association with chronic fatigue in primary Sjögren’s syndrome: a candidate gene study. (external link)
- Lencz, T; Knowles, Emily; Davies, G et al. (2014). Molecular genetic evidence for overlap between general cognitive ability and risk for schizophrenia: A report from the Cognitive Genomics consorTium (COGENT). (external link)
- Hill, Wayne David; Davies, Gail; Van De Lagemaat, Louie N. et al. (2014). Human cognitive ability is influenced by genetic variation in components of postsynaptic signalling complexes assembled by NMDA receptors and MAGUK proteins. (external link)
- Le Hellard, Stephanie; Steen, Vidar Martin (2014). Genetic architecture of cognitive traits. (external link)
- Thompson, Paul M; Stein, Jason L; Medland, Sarah E et al. (2014). The ENIGMA Consortium: Large-scale collaborative analyses of neuroimaging and genetic data. (external link)
- Reichborn-Kjennerud, Ted; Knudsen, Gun Peggy; Andreassen, Ole Andreas et al. (2014). A genome-wide association study of anorexia nervosa. (external link)
- Christoforou, Andrea; Espeseth, Thomas; Davies, Gail L. et al. (2014). GWAS-based pathway analysis differentiates between fluid and crystallized intelligence. (external link)
- Duarte Fernandes, Carla; Christoforou, Andrea; Giddaluru, Sudheer et al. (2013). A genetic deconstruction of neurocognitive traits in schizophrenia and bipolar disorder. (external link)
- Haldorsen, Karstein; Appel, Silke; Le Hellard, Stephanie et al. (2013). No association of primary Sjögren's syndrome with Fcγ receptor gene variants. (external link)
- Bolstad, Anne Isine; Le Hellard, Stephanie; Kristjansdottir, Gudlaug et al. (2012). Association between genetic variants in the tumour necrosis factor/lymphotoxin alpha/lymphotoxin beta locus and primary Sjogren's syndrome in Scandinavian samples. (external link)
- Ersland, Kari Merete; Christoforou, Andrea; Stansberg, Christine et al. (2012). Gene-based analysis of regionally enriched cortical genes in GWAS data sets of cognitive traits and psychiatric disorders. (external link)
- Espeseth, Thomas; Christoforou, Andrea; Lundervold, Astri et al. (2012). Imaging and cognitive genetics: the Norwegian Cognitive NeuroGenetics Sample. (external link)
- Christoforou, Andrea; Dondrup, Michael; Mattingsdal, Morten et al. (2012). Linkage-disequilibrium-based binning affects the interpretation of GWASs. (external link)
- Håvik, Bjarte; Degenhardt, Franziska A.; Johansson, Stefan et al. (2012). DCLK1 variants are associated across schizophrenia and attention deficit/hyperactivity disorder. (external link)
- Stein, Jason L; Medland, Sarah E; Vasquez, Alejandro Arias et al. (2012). Identification of common variants associated with human hippocampal and intracranial volumes. (external link)
- Fernø, Johan; Skrede, Silje; Vik-Mo, Audun Osland et al. (2011). Lipogenic effects of psychotropic drugs: focus on the SREBP system. (external link)
- Håvik, Bjarte; Le Hellard, Stephanie; Rietschel, Marcella et al. (2011). The Complement Control-Related Genes CSMD1 and CSMD2 Associate to Schizophrenia. (external link)
- Appel, Silke; Le Hellard, Stephanie; Bruland, Ove et al. (2011). Potential association of muscarinic receptor 3 gene variants with primary Sjögren's syndrome. (external link)
- Jassim, Goran; Fernø, Johan; Theisen, Frank M. et al. (2011). Association study of energy homeostasis genes and antipsychotic-induced weight gain in patients with schizophrenia. (external link)
- Davies, G.; Tenesa, A.; Payton, A. et al. (2011). Genome-wide association studies establish that human intelligence is highly heritable and polygenic. (external link)
- Le Hellard, Stephanie; Mühleisen, Thomas W.; Djurovic, Srdjan et al. (2010). Polymorphisms in SREBF1 and SREBF2, two antipsychotic-activated transcription factors controlling cellular lipogenesis, are associated with schizophrenia in German and Scandinavian samples. (external link)
- Le Hellard, Stephanie; Theisen, Frank M.; Haberhausen, Michael et al. (2009). Association between the insulin-induced gene 2 (INSIG2) and weight gain in a German sample of antipsychotic-treated schizophrenic patients: perturbation of SREBP-controlled lipogenesis in drug-related metabolic adverse effects?. (external link)
- Djurovic, Srdjan; Kähler, Anna Katarina; Kulle, Bettina et al. (2009). A possible association between schizophrenia and GRIK3 polymorphisms in a multicenter sample of Scandinavian origin (SCOPE). (external link)
- Le Hellard, Stephanie; Håvik, Bjarte; Espeseth, Thomas et al. (2009). Variants in doublecortin- and calmodulin kinase like 1, a gene up-regulated by BDNF, are Associated with memory and general cognitive abilities. (external link)
- Djurovic, Srdjan; Le Hellard, Stephanie; Kähler, Anna Katarina et al. (2009). Association of MCTP2 gene variants with schizophrenia in three independent samples of Scandinavian origin (SCOPE). (external link)
- Le Hellard, S; Muhleisen, TW; Djurovic, Srdjan et al. (2008). Polymorphisms in SREBF1 and SREBF2, two antipsychotic-activated transcription factors controlling cellular lipogenesis, are associated with schizophrenia in German and Scandinavian samples. (external link)
- Djurovic, Srdjan; Kähler, Anna Katarina; Kulle, Bettina et al. (2008). A possible association between schizophrenia and GRIK3 polymorphisms in a multicenter sample of Scandinavian origin (SCOPE). (external link)
- Le Hellard, Stephanie; Theisen, F.M.; Haberhausen, M et al. (2008). Association between the insulin-induced gene 2 (INSIG2) and weight gain in a German sample of antipsychotic-treated schizophrenic patients: pertubation of SREBP-controlled lipogenesis in drug-realted metabolic adverse effects?. (external link)
Poster
- Stavrum, Anne-Kristin; Szabo, Attila; Fernandes, Carla Patricia Duarte et al. (2020). Epigenetic Effects of THC and CBD in Neuronal Stem Cells. (external link)
- Bolstad, Anne Isine; Le Hellard, Stephanie; Kristjansdottir, GT et al. (2011). Association between tumor necrosis factor, lymphotoxin alpha and beta genetic variants and primary Sjögren`s syndrome in Scandinavian samples. (external link)
- Haldorsen, Karstein; Appel, Silke; Bruland, Ove et al. (2009). Fc receptor IIA, IIIA and IIIB single nucleotide polymorphisms and Fc receptor IIIB copy number variation: No association with primary Sjögren’s syndrome. (external link)
Errata
- Kaufmann, Tobias; van der Meer, Dennis; Doan, Nhat Trung et al. (2020). Publisher Correction: Common brain disorders are associated with heritable patterns of apparent aging of the brain (Nature Neuroscience, (2019), 22, 10, (1617-1623), 10.1038/s41593-019-0471-7). (external link)
- Davies, Gail; Lam, Max; Harris, Sarah E. et al. (2019). Author Correction: Study of 300,486 individuals identifies 148 independent genetic loci influencing general cognitive function (Nature Communications, (2018), 9, 1, (2098), 10.1038/s41467-018-04362-x). (external link)
Doctoral dissertation
- Tronstad, Rune Rose; Fiskerstrand, Torunn; Karlsen, Tom Hemming et al. (2019). Clinical and molecular effects of guanylate cyclase C-activation. (external link)
- Banerjee, Niladri; Le Hellard, Stephanie (2018). An evolutionary epigenetics approach to schizophrenia. (external link)
- Fernandes, Carla Patricia Duarte; Le Hellard, Stephanie (2015). A genetic study of schizophrenia and bipolar disorder. A cognitive endophenotype approach. (external link)
Reader opinion piece
- Lam, Max; Trampush, Joey W.; Yu, Jin et al. (2018). Multi-Trait analysis of gwas and biological insights into cognition: A response to Hill (2018). (external link)
- Christoforou, Andrea; Mattheisen, Manuel; Giddaluru, Sudheer et al. (2012). Linkage-Disequilibrium-Based Binning Misleads the Interpretation of Genome-wide Association Studies Response. (external link)
- Christoforou, Andrea; Mattheisen, Manuel; Giddaluru, Sudheer et al. (2012). Response to Zhu et al. (external link)
Abstract
- Steen, Vidar; Le Hellard, Stephanie; Espeseth, Thomas et al. (2013). Human cognitive ability is influenced by genetic variation in components of postsynaptic signaling complexes assembled by MAGUK proteins. (external link)
- Haldorsen, Karstein; Appel, Silke; Le Hellard, Stephanie et al. (2012). No association of primary Sjögren's Syndrome with Fc gamma? Receptor gene variants. (external link)
- Haldorsen, Karstein; Appel, Silke; Bruland, Ove et al. (2010). Fc gamma receptor IIA, IIIA and IIIB single nucleotide polymorphisms and Fc gamma receptor IIIB copy number variation: No association with primary Sjögren's syndrome. (external link)
Academic literature review
See a complete overview of publications in Cristin.
See my ORCID page: https://orcid.org/0000-0002-8085-051X