Anxiety with panic disorder linked to chromosome 9q in Iceland.
The results of a genomewide scan for genes conferring susceptibility to anxiety disorders in the Icelandic population are described. The aim of the study was to locate genes that predispose to anxiety by utilizing the extensive genealogical records and the relative homogeneity of the Icelandic population. Participants were recruited in two stages: (1) Initial case-identification by a population screening for anxiety disorders, using the Stamm Screening Questionnaire, was followed by aggregation into extended families, with the help of our genealogy database; and (2) those who fulfilled the diagnostic and family aggregation criteria underwent a more detailed diagnostic workup based on the Composite International Diagnostic Interview. Screening for anxiety in close relatives also identified additional affected members within the families. After genotyping was performed with 976 microsatellite markers, affected-only linkage analysis was done, and allele-sharing LOD scores were calculated using the program Allegro. Linkage analysis of 25 extended families, in each of which at least one affected individual had panic disorder (PD), resulted in a LOD score of 4.18 at D9S271, on chromosome 9q31. The intermarker distance was 4.4 cM on average, whereas it was 1.5 cM in the linked region as additional markers were added to increase the information content. The linkage results may be relevant not only to PD but also to anxiety in general, since our linkage study included patients with other forms of anxiety.
Thorgeirsson
Thorgeir E
TE
deCode Genetics, Reykjavík, Iceland. thorgeir@decode.is
Oskarsson
Högni
H
Desnica
Natasa
N
Kostic
Jelena Pop
JP
Stefansson
Jon G
JG
Kolbeinsson
Halldor
H
Lindal
Eirikur
E
Gagunashvili
Nikolai
N
Frigge
Michael L
ML
Kong
Augustine
A
Stefansson
Kari
K
Gulcher
Jeffrey R
JR
D001007:Anxiety / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D015897:Comorbidity; D008040:Genetic Linkage; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007055:Iceland / Q000453:epidemiology; D008126:Lod Score; D008403:Mass Screening; D018895:Microsatellite Repeats; D016584:Panic Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D011795:Surveys and Questionnaires
D005819:Genetic Markers