Genetic influences on endometriosis in an Australian twin sample. sueT@qimr.edu.au.
OBJECTIVE
To investigate the prevalence of and twin pair concordance for endometriosis.


METHODS
A questionnaire survey incorporating validation.


METHODS
An Australia-wide volunteer sample of female monozygotic (MZ) and dizygotic (DZ) twin pairs from the Australian National Health and Medical Research Council Twin Register.


METHODS
Twins were selected only on the basis of previous participation in twin research.


METHODS
Questionnaires were sent to 3,298 individuals. Information was requested from physicians named by consenting twins.


METHODS
Reported endometriosis, validated where possible by pathology or surgical report.


RESULTS
Three thousand ninety-six (94%) of the twins and 145 (82%) of the physicians responded to the survey. Two hundred fifteen twins reported endometriosis, for a prevalence rate of .07 among question respondents. Tetrachoric twin pair correlations for self-reported endometriosis (MZ: n = 854 and DZ: n = 493) were rMz = .46+/-.09 and rDz = .28 +/-.13. When available medical and pathology reports were included, they changed to rMz =.52 +/-.08 and rDZ = .19+/-.16, suggesting that 51% of the variance of the latent liability to endometriosis may be attributable to additive genetic influences.


CONCLUSIONS
These findings support the hypothesis that genes influence liability to endometriosis.
Treloar
S A
SA
Cooperative Research Centre for Discovery of Genes for Common Human Diseases, Queensland Institute of Medical Research, Brisbane, Australia. sueT@qimr.edu.au
O'Connor
D T
DT
O'Connor
V M
VM
Martin
N G
NG
D000293:Adolescent; D000328:Adult; D001315:Australia; D004200:Diseases in Twins; D004715:Endometriosis / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D010641:Phenotype; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic