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Seasonal changes in mood and diurnal preference are two well-characterized chronobiological phenotypes in major depressive disorder (MDD) and bipolar disorder (BD). The biological mechanisms regulating physiological changes related to seasonality and chronotype involve several genes known as "clock" or circadian genes. Our goal was to study the relationship between the polygenic risk score (PRS) obtained from a set of clock genes and chronobiological traits in patients with mood disorders. The sample included 445 patients with mood disorders (256 MDD; 189 BD). Seasonality was assessed using the Seasonal Pattern Assessment Questionnaire (SPAQ), and chronotype was assessed using the Horne and Östberg Morningness-Eveningness Questionnaire. We selected 248 single nucleotide polymorphisms located within 19 genes. PRS for both MDD and BD was calculated using the Psychiatric Genetics Consortium latest datasets as discovery samples. Another PRS was calculated using results from a genome-wide association study focusing on chronotype. SPAQ results were significantly associated with MDD-PRS (p = 0.037) and chronotype-PRS (p = 0.019), which also showed a significant interaction with age (p = 0.039). No significant association was observed between the measured PRS and chronotype. Our results reflect that small effect variants associated with MDD and chronotype within clock genes are associated with seasonality traits in patients with mood disorders, further explaining the mechanism through which the circadian system might influence mood disorder clinical presentation. Future studies measuring PRS from specific gene sets and focusing on biological endophenotypes will help to elucidate the pathways from genetic variations to clinical outcome.

Objective Blindness has rarely been described in the eating disorder (ED) literature. In case reports in which this condition has been reported before an ED, it was concluded that visual body image was not essential for the development of the ED. This is the first report in which bulimia nervosa (BN) and its treatment in a blind woman were described. Method We report a single diagnosed and treated case of BN in a blind, 47-year-old Spanish woman. This case presented as its main characteristics the late onset of the ED, restrictive dieting, binging, and consequent purging behavior characterized by vomiting and great difficulties of coping with stress. From the beginning, the woman's body image was not essential. The treatment consisted of 21 individual outpatient sessions, which followed a non–symptom-oriented cognitive-behavioral approach, in which problem solving and stress management strategies were employed. Results Before, after the treatment, and at the 6-month and 1-year follow-up, the clinical evolution of the patient was assessed. Conclusion Although a few descriptions of single case reports on blindness in individuals with anorexia nervosa (AN) have already been reported in the literature, to the authors' knowledge, this is the first reported case in which this condition and its treatment have specifically been reported in an individual with BN. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006

Circadian rhythms disruptions, including abnormalities of circadian phase position and melatonin secretion, have been described in major depression (MD). Arylalkylamine N-acetyltransferase (AANAT) is a key enzyme of the melatonin pathway involved in circadian oscillations of melatonin levels. We assessed the contribution of AANAT gene variability to susceptibility to MD considering common and rare genetic variations through a sequential sequencing and single nucleotide polymorphism (SNP)-based genotyping approach in a sample of 445 unrelated patients with MD (257 unipolar MD, 188 bipolar depression) and 440 community-based screened control subjects. We identified 17 sequence changes, thirteen of which represented novel sequence variations. We did not observe an over-representation of patients carrying rare variants compared with the healthy controls. Common variants (MAF > 2%) were included in a case–control association analysis that showed significant association after multiple testing correction of two SNPs located in the promoter region of AANAT with MD: rs3760138 (P = 0.00006) and rs4238989 (P = 0.005). Multimarker analysis found significant associations between two three-marker protective haplotypes and a susceptibility three-marker haplotype containing the rare alleles of rs3760138-rs4238989-rs8150 and MD. We present evidence of the association of genetic variability in the AANAT gene with susceptibility to MD. Our results support the hypothesis that the melatonin-signaling pathway and circadian clock mechanisms may contribute to the pathophysiology of MD.