Skip to main content


Research Groups

Håkan Karlsson, Ph.D.

Håkan Karlsson

Håkan Karlsson, M.D., Ph.D.

Research Focus

Our research efforts are focused on the etiology and pathogenesis of schizophrenia. For these purposes we use Swedish registers and biobanks as well as biological samples obtained from patients during different stages of the disease.

In such samples we try to identify risk-factors and markers of disease onset and progression. In experimental animal models we investigate how these factors interact to affect behavior, primarily relating to cognition. Based on observations of transcriptional aberrancies of regions of the human genome harboring elements in the W family of human endogenous retroviruses (HERV-W) in patients suffering their first episode of schizophrenia we have a special interest in investigating why and when such regions are transcribed in different human tissues.

Selected Publications

Dalman C, Allebeck P, Gunnell D, Harrison G, Kristensson K, Lewis G, Lofving S, Rasmussen F , Wicks S, Karlsson H.

Infections in CNS during childhood and the risk of subsequent psychotic illness. A cohort study of more than one million Swedish subjects.

American Journal of Psychiatry 165: 59-65, 2008

Yao Y, Schröder J, Nellåker C, Bottmer C, Bachmann S, Yolken RH, Karlsson H.

Elevated levels of HERV-W transcripts in blood cells from patients with first episode schizophrenia.

Genes, Brain & Behavior 7: 103-112, 2007

Nellaker C, Yao Y, Jones-Brando L, Mallet F, Yolken RH, Karlsson H.

Transactivation of elements in the human endogenous retrovirus W family by viral infection.

Retrovirology 3: 44, 2006

Karlsson H, Schröder J, Bachmann S, Bottmer C, Yolken RH.

HERV-W related RNA detected in plasma from individuals with recent onset schizophrenia or schizoaffective disorder.

Molecular Psychiatry 9: 12-13, 2004

Karlsson H, Bachmann S, Schröder J, McArthur J, Torrey EF and Yolken RH.

Retroviral RNA identified in the cerebrospinal fluids and brains of individuals with schizophrenia.

Proceedings of the National Academy of Sciences U.S.A. 98: 4634-4639, 2001

Researcher Håkan Karlsson

08-524 878 32
08-32 53 25
Department of Neuroscience
Karolinska Institutet
Retzius väg 8
S-17177 Stockholm, Sweden