The ACE I/D polymorphism was genotyped in a sample of 102 German patients with panic disorder with or without agoraphobia as well as a healthy German control group matched with regard to age and sex (n = 102).
Furthermore, no association was demonstrated between this A2aAR polymorphism and either mitral-valve prolapse or agoraphobia in panic-disorder patients.
Furthermore, no association was demonstrated between this BDNF polymorphism and either mitral valve prolapse or agoraphobia in panic disorder patients.
We found, however, a prominent association between severity of panic- and agoraphobia symptoms and an exonic SNP (rs3817190) in the CaMKKb gene and a trend for association with an exonic SNP in P2RX7 (rs1718119) with severity scores in the panic- and agoraphobia scale.
Indeed, heightened concentrations of inflammatory signals, including cytokines and C-reactive protein, have been described in posttraumatic stress disorder (PTSD), generalized anxiety disorder (GAD), panic disorder (PD), and phobias (agoraphobia, social phobia, etc.).
Panic change was strongly related to improvements in agoraphobia (r = 0.70) and MDD (r = 0.53), moderately related for GAD (r = 0.31), and not significantly related for SAD (r = 0.20).
While all subtypes were associated with poorer mental health and particularly more depression, severe sleep problems appeared to be the sleep subtype seen in agoraphobia and GAD, while delayed sleep had no specific associations.
As one of the first findings being confirmed by genome-wide association studies for the phenotype of panic disorder and agoraphobia, allelic variation in a gene coding for the glycine receptor beta subunit (GLRB) has recently been associated with increased neural fear network activation and enhanced acoustic startle reflexes.
We followed up on this finding in a larger dimensional ACQ sample (N=2547) and in independent samples with a dichotomous AG phenotype based on the Symptoms Checklist (SCL-90; N=3845) and a case-control sample with the categorical phenotype PD/AG (N<sub>combined</sub> =1012) obtaining highly significant P-values also for GLRB single-nucleotide variants rs17035816 (P=3.8 × 10<sup>-4</sup>) and rs7688285 (P=7.6 × 10<sup>-5</sup>).
Preclinical studies point to a pivotal role of the orexin 1 (OX<sub>1</sub>) receptor in arousal and fear learning and therefore suggest the HCRTR1 gene as a prime candidate in panic disorder (PD) with/without agoraphobia (AG), PD/AG treatment response, and PD/AG-related intermediate phenotypes.
In sum, the present results provide converging evidence for an involvement of HCRTR1 gene variation in the etiology of PD/AG and PD/AG-related traits as well as treatment response to CBT, supporting future therapeutic approaches targeting the orexin-related arousal system.
We investigated a possible association between this 5-HT1A gene promoter polymorphism and panic disorder by genotyping the 1019C>G single nucleotide polymorphism in 134 panic-disorder patients with and without agoraphobia and matched 134 controls.
In this association study, the 1019C/G (rs6295) promoter polymorphism of the 5-HT1A receptor G/G genotype was associated with PD without AP in a Japanese population.
We followed up on this finding in a larger dimensional ACQ sample (N=2547) and in independent samples with a dichotomous AG phenotype based on the Symptoms Checklist (SCL-90; N=3845) and a case-control sample with the categorical phenotype PD/AG (N<sub>combined</sub> =1012) obtaining highly significant P-values also for GLRB single-nucleotide variants rs17035816 (P=3.8 × 10<sup>-4</sup>) and rs7688285 (P=7.6 × 10<sup>-5</sup>).
Subjects provided self-ratings of anxiety using the SCL-90-R, from which we used the phobia subscale, covering anxiety symptoms related to those of panic and agoraphobia spectrum.
However, a higher frequency of longer allele genotypes of the MAOA promoter region was observed in female PD patients with agoraphobia than in female controls (p = 0.016).