Male-mediated teratogenesis: spectrum of congenital malformations in the offspring of A/J male mice treated with ethylnitrosourea

Teratogenesis, Carcinogenesis, and Mutagenesis
T Nagao, K Fujikawa

Abstract

Male mice of inbred strain A/J were intraperitoneally treated with ethylnitrosourea (ENU). On day 64-82 posttreatment, the males were mated with untreated virgin females of the same strain. Copulation involved sperm that were spermatogonial stem cells at the time of treatment. On day 18 of gestation, viable fetuses were inspected for external malformations. The most common malformation to occur spontaneously in the control group was cleft palate or cleft lip. Similarly, in the ENU-treated series, cleft palate or cleft lip was the predominant malformation, the frequency (15%) of which was significantly increased in the highest dose group (5 x 50 mg/kg) compared to control (8%). Based on these results and other data, we propose that a large fraction of external malformations in fetuses from mutagenized paternal germ cells are a result of increased yields of spontaneously occurring malformations.

Related Concepts

Related Feeds

Birth Defects

Birth defects encompass structural and functional alterations that occur during embryonic or fetal development and are present since birth. The cause may be genetic, environmental or unknown and can result in physical and/or mental impairment. Here is the latest research on birth defects.