Twin pairs born 1953–82 registered in the new Danish Twin Register | 20 888 |
Twin pairs with IDDM identified by questionnaire: | 102 |
One or both unwilling to participate | 39 |
One twin partner had died | 7 |
One twin partner had emigrated | 5 |
No response in one twin partner | 3 |
Twin pairs investigated: 17 MZ pairs, 15 DZss pairs, and 16 DZos pairs | 48 |
Twin pairs excluded from paired analysis: | |
Did not want pupils dilated (MZ) | 1 |
Ocular trauma in one eye (DZos) | 1 |
Corneal transplantation in one eye (DZss) | 1 |
Twin pairs in paired analysis: 16 MZ , 14 DZss, and 15 DZos pairs | 45 |
↵Of these, two twins (MZ + DZss) did not cooperate with ultrasonic measurements.