This analysis is a follow-up to an earlier investigation of 182 genes selected as likely candidate genetic variations conferring susceptibility to anorexia nervosa (AN). As those initial case-control results revealed no statistically significant differences in single nucleotide polymorphisms, herein we investigate alternative phenotypes associated with AN. In 1762 females using regression analyses we examined: (1) lowest illness-related attained body mass index; (2) age at menarche; (3) drive for thinness; (4) body dissatisfaction; (5) trait anxiety; (6) concern over mistakes; and (7) the anticipatory worry and pessimism vs. uninhibited optimism subscale of the harm avoidance scale. After controlling for multiple comparisons, no statistically significant results emerged. Although results must be viewed in the context of limitations of statistical power, the approach illustrates a means of potentially identifying genetic variants conferring susceptibility to AN because less complex phenotypes associated with AN are more proximal to the genotype and may be influenced by fewer genes.

Objective

We investigated sociodemographic characteristics in women with and without lifetime eating disorders.

Method

Participants were from a multi-site international study of eating disorders (N = 2096). Education level, relationship status, and reproductive status were examined across eating disorder subtypes and compared with a healthy control group.

Results

Overall, women with eating disorders were less educated than controls, and duration of illness and age of onset were associated with educational attainment. Menstrual status was associated with both relationship and reproductive status, but eating disorder subtypes did not differ significantly from each other or from healthy controls on these dimensions.

Conclusion

Differences in educational attainment, relationships, and reproduction do exist in individuals with eating disorders and are differentially associated with various eating disorder symptoms and characteristics. These data could assist with educating patients and family members about long-term consequences of eating disorders.

We performed association studies with 5,151 SNPs that were judged as likely candidate genetic variations conferring susceptibility to anorexia nervosa (AN) based on location under reported linkage peaks, previous results in the literature (182 candidate genes), brain expression, biological plausibility, and estrogen responsivity. We employed a case–control design that tested each SNP individually as well as haplotypes derived from these SNPs in 1,085 case individuals with AN diagnoses and 677 control individuals. We also performed separate association analyses using three increasingly restrictive case definitions for AN: all individuals with any subtype of AN (All AN: n = 1,085); individuals with AN with no binge eating behavior (AN with No Binge Eating: n = 687); and individuals with the restricting subtype of AN (Restricting AN: n = 421). After accounting for multiple comparisons, there were no statistically significant associations for any individual SNP or haplotype block with any definition of illness. These results underscore the importance of large samples to yield appropriate power to detect genotypic differences in individuals with AN and also motivate complementary approaches involving Genome-Wide Association (GWA) studies, Copy Number Variation (CNV) analyses, sequencing-based rare variant discovery assays, and pathway-based analysis in order to make up for deficiencies in traditional candidate gene approaches to AN.

Anorexia nervosa is a perplexing illness with the highest mortality rate of any psychiatric disease. In this paper, we review the genetic research on anorexia nervosa (AN). Family studies have demonstrated that anorexia nervosa is familial, and twin studies have indicated that additive genetic factors contribute to the familial aggregation. Molecular genetic research, including genomewide linkage and case control association studies, have not been successful in identifying DNA variants that are unequivocally involved in the etiology of AN. We provide a critical appraisal of these studies and discuss methodological issues that may be implicated in conflicting results. Furthermore, we discuss issues relevant to genetic research such as the importance of phenotypic refinement, the use of endophenotypes, and the implications for nosology and genetic analysis. Finally, the future of genetic research for AN is discussed in terms of genomewide association studies (GWAS) and the need for establishing large samples.