I read with interest the commentary on genetic epidemiology and congenital malformation by Hobbs and colleagues in the April issue of the ARCHIVES. It was a nice review and update for a general pediatrician who has been in practice now for 16 years.
However, on page 317, there may have been a mistake in lines 5 and 6, which was repeated in lines 9 and 10. The statement was that "dizygotic twins share half of their genes at most," followed by "dizygotic twins would share the malformation in, at most, 50% of twins studied."
Jantz JW. Genetics Update. Arch Pediatr Adolesc Med. 2002;156(10):1058. doi: