Bivariate analysis of disordered eating characteristics in adolescence and young adulthood.
OBJECTIVE
We examined the etiology of two disordered eating characteristics.


METHODS
Participants included 1,470 female adolescent and young adult twins and their female nontwin siblings. Phenotypic factor analyses of a seven-item eating pathology screening tool yielded two factors: weight and shape concerns and behaviors (WSCB) and binge eating (BE). Univariate and bivariate extended twin analyses (including cotwins and nontwin siblings) were used to estimate the magnitude of genetic and environmental influences on these characteristics.


RESULTS
Analyses indicated that individual differences in WSCB and BE could be explained by additive genetic influences (a² = 0.43 (95% CI: 0.33-0.52) and 0.49 (95% CI: 0.36-0.58), respectively), with the remaining variance due to nonshared environmental influences. The genetic correlation between WSCB and BE was estimated at 0.64; the nonshared environmental correlation was estimated at 0.27.


CONCLUSIONS
These results corroborate previous findings on genetic and environmental influences on disordered eating characteristics and suggest that findings can be extended to nontwin populations.
Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado, USA. melissa.munn@colorado.edu
Melissa A
MA
Munn
Michael C
MC
Stallings
Soo Hyun
SH
Rhee
Laura E
LE
Sobik
Robin P
RP
Corley
Sally Ann
SA
Rhea
John K
JK
Hewitt
D000293:Adolescent; D000328:Adult; D056912:Binge-Eating Disorder / Q000235:genetics*; D001828:Body Image; D004777:Environment; D005260:Female; D006801:Humans; D010641:Phenotype; D055815:Young Adult