Narrator: This is Science Today. Researchers at the University of California, San Francisco, recently uncovered at the molecular level how cigarette smoke affects early human development. Study leader Harold Bernstein says they identified a number of pathways that play a role in this process, including a protein called nodal.
Bernstein: What we found was that tobacco smoke components disturb this nodal signaling pathway, and we also found that certain components of tobacco, like nicotine, were responsible for some of the alterations in how nodal signaling occurred.
Narrator: But in further tests, even without nicotine, tobacco smoke still upset nodal signaling. This suggests that other tobacco smoke components likely have a negative effect as well.
Bernstein: There's been such an emphasis on the effects of nicotine, especially because of its effects on blood vessels. And one of the things these studies showed is that there are in fact things other than nicotine that probably have similarly bad effects.Narrator: For Science Today, I'm Larissa Branin.