Gene expression in teratogenic exposures: a new approach to understanding individual risk. Mus musculus

The phenomenon of partial or incomplete penetrance is common to many paradigms of exposure to teratogens, where only some of the exposed individuals exhibit developmental defects. We here argue that the most widely used experimental approaches in reproductive toxicology do not take partial penetrance into account, and are thus likely to miss differences between affected and unaffected individuals that contribute to susceptibility for teratogenesis. We propose that focus on the variation between exposed individuals could help to discover factors that may play a causative role for abnormal developmental processes that occur with incomplete penetrance. Overall design: Total RNA was extracted from individual embryos E10.5 derived from normal and diabetic pregnancies. A total of 8 sample pools were created, 4 resultiing from normal (C1-C4) and 4 from diabetic (E1-E4) pregnancies. Each pool consisted of RNA from 4 embryos obtained from 4 different pregnancies. Samples E5-E8 consisted of individual embryos with NT defects obtained from diabetic pregnancies.