Major Affective Disorder 5
For a phenotypic description and a discussion of genetic heterogeneity of bipolar disorder, see 125480.
MappingJamra et al. (2007) performed a genomewide interaction and locus heterogeneity linkage scan in bipolar affective disorder (BPAD), using a large linkage dataset (52 families of European descent; 448 participants and 259 affected individuals). The results provided the strongest evidence of interaction between BPAD genes on chromosome 2q22-q24 (MAFD5) and 6q23-q24 (MAFD6; 611536), which was observed symmetrically in both directions; nonparametric lod (NPL) scores of 7.55 on 2q and 7.63 on 6q; P less than 0.0001 and P = 0.0001, respectively, after a genomewide permutation procedure. The second-best BPAD interaction evidence was observed between 2q22-q24 and 15q26. Here, Jamra et al. (2007) also observed a symmetric interaction. Whereas chromosome 6q23-q24 showed evidence within the 1-dimensional linkage scan, the chromosome 2q22-q24 locus was detectable only in the 2-dimensional linkage scan. With use of a 1-lod interval, the underlying BPAD gene on 2q22-q24 is located between 150 and 166 cM corresponding to approximately 137 and 157 Mb, respectively, according to NCBI36. Jamra et al. (2007) concluded that the MAFD5 locus harbors a gene that interacts epistatically with a second risk locus on chromosome 6q23-q24.