In utero sister chromatid exchange analysis for detection of transplacental mutagens

FETAL exposure to agents which damage DNA can result in birth anomalies, cancer and inherited abnormalities. In the present report we describe a new approach for the detection of fetal DNA damage through the enumeration of sister chromatid exchanges (SCE) in mouse fetal chromosomes. SCE can be identified as reciprocal exchanges of fluorescent intensities betweeen sister chromatids in metaphase cells which have divided twice in the presence of bromodeoxyuride (BrdU) (Fig. 1). Analysis of SCE has been shown to be a sensitive and reproducible means of detecting chemical mutagens and carcinogens 1–9 .