title: Anhedonia in schizophrenia: a distinct familial subtype?
abstract: Failures to replicate results in psychiatric genetics might be due to our inability to define the heritable phenotype. Instead of relying entirely on classical nosographical approaches, the use of a candidate symptom approach to identify more homogeneous forms of diseases among affected subjects and subclinical traits among first-degree relatives may increase genetic validity. Anhedonia may be a marker for subjects at risk of schizophrenia or schizophrenia spectrum disorders. We compared the familiality of anhedonia characterized by a high level of physical anhedonia (score above 23) in a sample of schizophrenic probands (N=80) and their relatives (N=78), with that in bipolar patients (N=109), their relatives (N=33) and normal controls (N=94). We identified a subform of schizophrenia characterized by highly anhedonic schizophrenic probands with a three-fold higher familial risk of schizophrenia and schizophrenic spectrum disorders. We also found that their first-degree relatives had a high level of anhedonia. An intrafamilial correlation analysis confirmed the familial nature of anhedonia. Our data suggest that anhedonia is a candidate symptom for schizophrenia. Refining phenotype definition by studying subgroups of anhedonic and non-anhedonic probands with relevant candidate genes might be fruitful.
authors.affiliation: Service de Psychiatrie Adulte du Pr. Rouillon, Hôpital Albert Chenevier et Henri Mondor (AP-HP), 40 rue Mesly, 94000 Creteil, France. schurhof@ext.jussieu.fr
authors.forename: Franck
authors.initials: F
authors.lastname: Schürhoff
authors.forename: Andrei
authors.initials: A
authors.lastname: Szöke
authors.forename: Frank
authors.initials: F
authors.lastname: Bellivier
authors.forename: Cristina
authors.initials: C
authors.lastname: Turcas
authors.forename: Michelle
authors.initials: M
authors.lastname: Villemur
authors.forename: Jean
authors.initials: J
authors.lastname: Tignol
authors.forename: Frédéric
authors.initials: F
authors.lastname: Rouillon
authors.forename: Marion
authors.initials: M
authors.lastname: Leboyer
mesh_terms: D000328:Adult; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000150:complications* / Q000235:genetics*; D010641:Phenotype; D012559:Schizophrenia / Q000150:complications* / Q000235:genetics* / Q000534:rehabilitation