1 Departments of Pediatrics and Epidemiology and International Health University of California, San Francisco, CA 94143
In Reply.
I expected that Dr Nora might respond to my paper, and I appreciate the opportunity to address his thoughtful comments.
Dr Nora and I are in agreement on several points: that there is a large element of chance in the etiology of congenital heart defects, that the "rough approximations" for multifactorial inheritance he used in the past are wrong and should be abandoned, that continued vigilance is essential to identify new teratogens and genetic syndromes, and that parents should not feel guilty about congenital heart defects in their offspring.