TY  - JOUR
T1  - A twin study of erectile dysfunction
AU  - Fischer ME, Vitek M, Hedeker D, Henderson WG, Jacobsen SJ, Goldberg J
Y1  - 2004/01/26
N1  - 10.1001/archinte.164.2.165
JO  - Archives of Internal Medicine
SP  - 165
EP  - 168
VL  - 164
IS  - 2
N2  - Background 
    The extent of genetic influence on erectile dysfunction (ED) is unknown. This study determines the contribution of heredity to ED in a sample of middle-aged men.Methods 
    A classical twin study was conducted in the Vietnam Era Twin Registry, a national sample of male-male pairs (mean birth year, 1949) who served on active duty during the Vietnam era (1965-1975). A 1999 male health survey was completed by 890 monozygotic (MZ) and 619 dizygotic (DZ) pairs. The prevalence and heritability of 2 self-report indicators of ED, difficulty in having an erection and in maintaining an erection, are estimated.Results 
    The prevalence of difficulty in having an erection is 23.3% and in maintaining an erection is 26.7%. Twin correlations for dysfunction in having an erection are 0.35 (95% confidence interval [CI], 0.28-0.41) in MZ and 0.17 (95% CI, 0.09-0.27) in DZ pairs. For dysfunction in maintaining an erection, the twin correlations in MZ and DZ pairs are 0.39 (95% CI, 0.32-0.45) and 0.18 (95% CI, 0.09-0.27), respectively. The estimated heritability of liability for dysfunction in having an erection is 35% and in maintaining an erection is 42%. The heritable influence on ED remained significant after adjustment for ED risk factors.Conclusions 
    The present study demonstrates an ED-specific genetic component that is independent of genetic influences from numerous ED risk factors. The results suggest that future molecular genetic studies to identify ED-related polymorphisms are warranted.
SN  - 0003-9926
M3  - doi: 10.1001/archinte.164.2.165
UR  - http://dx.doi.org/10.1001/archinte.164.2.165
ER  -