Article

Bipolar disorder and panic disorder in families: an analysis of chromosome 18 data. Am J Psychiatry

Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
American Journal of Psychiatry (Impact Factor: 13.56). 07/1998; 155(6):829-31.
Source: PubMed

ABSTRACT The authors performed an analysis of their published chromosome 18 linkage data on 28 families in which there was bipolar disorder to test the potential of comorbid panic disorder to define a genetic subtype of bipolar disorder.
Families ascertained through probands with bipolar I disorder were stratified into three groups based on a history of panic disorder, panic attacks, or no panic attacks in the probands. Multipoint nonparametric linkage analysis was performed on data from bipolar I and II family members in each group.
Linkage scores for five consecutive 18q marker loci were highest in the families of the probands with panic disorder and lowest for the families of the probands without panic attacks.
This study supports the authors' previously reported clinical hypothesis of a genetic subtype of bipolar disorder identified by comorbid panic disorder. The hypothesis merits prospective testing.

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    • "Accordingly, molecular genetic linkage studies analyzing cosegregation of particular genetic markers with the disease of interest in pedigrees of affected families have yielded evidence for a variety of potential risk loci for anxiety disorders, e.g. for panic disorder on chromosomes 1p, 4q, 7p, 9q, 11p, 15q and 20p as well as on chromosomes 18, 13 and 22, respectively (Crowe et al., 1987; Fyer et al., 2006; Gelernter et al., 2001; Hamilton et al., 2003; Kaabi et al., 2006; Knowles et al., 1998; MacKinnon et al., 1998; Thorgeirsson et al., 2003), and for social or specific phobia on chromosomes 16q and 14p (Arnold et al., 2004; Gelernter et al., 2003, 2004; Smoller et al., 2008a; Stein et al., 1998). Also, molecular genetic association studies investigating the allelic frequency of a particular marker in an a-priori candidate gene in a patient sample as compared to a sample of healthy controls have reported a multitude of positive findings in panic disorder, particularly in genes coding for the cholezystokinin B (CCK- B) receptor (Hosing et al., 2004; Kennedy et al., 1999), the monoamine oxidase A (MAO-A) (Deckert et al., 1999), the catechol- O-methyltransferase (COMT) (Hamilton et al., 2002, Domschke et al., 2004; Rothe et al., 2006; Domschke et al., 2007), the serotonin receptor 1A (5-HT1A) (Huang et al., 2004; Rothe et al., 2004), the serotonin transporter (5-HTT) (Maron et al., 2004, 2005), the adenosine A2A receptor (Deckert et al., 1998; Hamilton et al., 2004), Rgs2 (Leygraf et al., 2006; Smoller et al., 2008c) and in the neuropeptide Y gene system (Domschke et al., 2008a). "
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