Ninety-four female-female twins underwent a trans-abdominal ultrasound
examination to detect polycystic ovaries. The scans of 52 individuals
showed normal ovaries and 42 had evidence of polycystic ovaries. All
the subjects were sent a bulimia investigation test (Edinburgh) (BITE)
questionnaire for abnormal eating behavior. A total of 74 responses w
as received (79%). Overall, 76% of women with polycystic ovaries had a
n abnormal BITE score and their mean BITE score showed a significant i
ncrease compared to those with normal ovaries. Also, model fitting ana
lysis suggested a strong genetic effect for bulimia using the BITE sco
ring system, and it provided strong evidence of a significant influenc
e of environmental factors in the severity score of bulimia.