A novel stroke locus identified in a northern Sweden pedigree: linkage to chromosome 9q31-33.
OBJECTIVE
The population of northern Sweden is characterized by reduced genetic diversity and a high incidence of stroke. We sought to reduce genetic variation further, using genealogic analysis in a set of nuclear families affected by stroke, and we subsequently performed a genome-wide scan to identify novel stroke susceptibility loci.


METHODS
Through genealogy, 7 nuclear families with a common ancestor, connected over 8 generations, were identified. A genome-wide scan using 449 microsatellite markers was performed with subsequent haplotype analyses.


RESULTS
A maximum allele-sharing lod score of 4.81 on chromosome 9q31-q33 was detected. Haplotype analysis identified a common 2.2-megabase interval in the chromosomal region in 4 of the nuclear families, where an overrepresentation of intracerebral hemorrhage was observed.


CONCLUSIONS
We have identified a novel susceptibility locus for stroke. Haplotype analysis suggests that a shared genetic factor is of particular importance for intracerebral hemorrhage.
Janunger
T
T
Department of Medical Biosciences, Division of Medical and Clinical Genetics, Umeå University, Sweden.
Nilsson-Ardnor
S
S
Wiklund
P-G
PG
Lindgren
P
P
Escher
S A
SA
Lackovic
K
K
Nilsson
A K
AK
Stegmayr
B
B
Asplund
K
K
Holmberg
D
D
D000368:Aged; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study / Q000379:methods; D006239:Haplotypes; D006801:Humans; D008126:Lod Score; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D020521:Stroke / Q000000981:diagnostic imaging* / Q000235:genetics*; D013548:Sweden; D014057:Tomography, X-Ray Computed / Q000379:methods