Genetic and environmental influences on anorexia nervosa syndromes in a population–based twin sample

Abstract

Findings support previous research indicating significant genetic and non-shared environmental influences on AN syndromes.

Assessing the heritability of anorexia nervosa symptoms using a marginal maximal likelihood approach

“…The overall heritability of AN was moderate, and lower than that obtained in both the only previous study to examine the full AN diagnosis , as well as that found in studies using broader definitions of AN (e.g., Klump et al, 2001;Kortegaard et al, 2001;Wade et al, 2000). However, the current estimate is within the (albeit wide) CI obtained in the Bulik et al study.…”

“…Thus, the relatively higher influence of E found in the current study, compared to others which have evaluated AN at the diagnostic level (e.g., Bulik et al, 2006;Klump et al, 2001;Kortegaard et al, 2001;Wade et al, 2000) could reflect both measurement error and nonshared environmental experiences. It is not possible to determine exactly what proportion of variance accounted for by E in this study is due to either true unshared experiences or to measurement error.…”

“…Bulik et al's findings also suggested that unshared environment significantly influences AN symptomatology (i.e., unshared environment accounted for about one-third of the variance in AN). Similarly, studies of broadly-defined AN have supported the role of genetic factors in the etiology of this pernicious disorder (Klump, Miller, Keel, McGue, & Iacono, 2001;Kortegaard, Hoerder, Joergensen, Gilberg, & Kyvik, 2001;Wade, Bulik, Neale, & Kendler, 2000).…”

A genome-wide association study on common SNPs and rare CNVs in anorexia nervosa

“…24,25 Genetic epidemiological studies have documented the familiality of AN (relative risk 11.3 in first-degree relatives of AN probands) 26,27 and the estimated twin-based heritability of AN ranges from 33 to 84%. [28][29][30][31][32] Genome-wide linkage studies did not narrow the genomic search space in a compelling manner. [33][34][35] Findings from candidate gene studies of AN resemble those for most complex biomedical diseases-initial intriguing findings diminished by the absence of rigorous replication.…”

Anorexia nervosa: Definition, epidemiology, and cycle of risk

“…44,45,[88][89][90][91][92][93] Nonetheless, environment may play an important role in the expression of underlying genetic predispositions. The concept of gene-environment correlation may be highly relevant to understanding how the cycle of risk is perpetuated.…”