Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The control 9-day embryo (a) demonstrates the normal appearance of the head and ventral body wall. An embryo of the same age treated with HcysTD (b) is grossly abnormal. There is a lower beak (arrowhead) but no upper beak, indicating a failure of closure of the face. The cranium is completely open and brain tissue is exposed (b), as with anencephaly. The ventral wall of the thorax is open and the heart is extruded as in ectopia cordis (h).
