Linkage analysis in bipolar pedigrees adds support for a susceptibility locus on 21q22.
Several studies provide suggestive evidence of a susceptibility locus for bipolar disorder at chromosome 21q22-23. In an attempt to replicate these findings, we have analyzed linkage to 11 polymorphic markers from this region in 18 Bulgarian pedigrees with affective disorder. Two-point linkage analysis under assumption of homogeneity and a dominant model with reduced penetrance produced modest positive values for some of the markers tested under a 'narrow' phenotype definition, including bipolar I and II, and schizoaffective disorder. The maximum two-point score (lod=1.76, theta=0.00) was at marker D21S1919. Non-parametric linkage analysis under the same phenotype model, yielded positive NPLall values (P<0.05) over the region between markers D21S211 and D21S416, with a peak at D21S1252 (NPL Zall=2.32, P=0.0003). The multipoint lod score (GENEHUNTER) reached a suggestive value for linkage (lod=2.10) also at marker D21S1252. The results under a recessive model were completely negative. These data add to the evidence for the existence of a susceptibility locus for bipolar affective disorder on chromosome 21q22.
Kaneva
Radka P
RP
Laboratory of Molecular Pathology, University Hospital of Obstetrics, Medical University Sofia, Bulgaria. kaneva@medfac.acad.bg
Chorbov
Vesselin M
VM
Milanova
Vihra K
VK
Kostov
Christian S
CS
Nickolov
Kaloian I
KI
Chakarova
Christina F
CF
Stoyanova
Vesela S
VS
Nikolova-Hill
Amelia N
AN
Krastev
Stefan K
SK
Onchev
George N
GN
Kremensky
Ivo M
IM
Kalaydjieva
Luba V
LV
Jablensky
Assen V
AV
D001714:Bipolar Disorder / Q000235:genetics*; D002031:Bulgaria; D002170:Canada; D002874:Chromosome Mapping; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D007585:Jews; D008126:Lod Score; D008297:Male; D008957:Models, Genetic; D010375:Pedigree; D014481:United States