Table 2

Patient characteristics of the 47 twin pairs analysed

Monozygotic twin pairsDizygotic twin pairs
Concordant (n=15)Discordant (n=5)Total (n=20)Concordant (n=3)Discordant (n=24)Total (n=27)
Mean age (y):
    At enrolment19.617.219.016.014.514.7
    At onset in the index twin 6.8 7.8 2.3 4.9
    At onset in the 2nd twin 9.6 3.7
    Time elapsed to the onset of CD in the 2nd twin 1.3 2.4
Male/male pairs 5 1 6 0 8 8
Female/female pairs10 414 1 6 7
Opposite sex pairs 21012