MONOALLELIC EXPRESSION OF IGF2 AT THE HUMAN FETAL MATERNAL BOUNDARY

IGF2 is expressed in both placental and decidual tissues, enabling an analysis of the parental imprinting over the fetomaternal boundary. Ev idence is provided that IGF2 is monoallelically expressed in both plac enta and pregnant, as well as nonpregnant, endometrium. These observat ions suggest that the maternally derived IGF2 allele is inactivated du ring germline transmission. Comparison of promoter usage in decidua an d placental samples shows that the P3 promoter appears to regulated in dependently of the others. These observations are discussed with respe ct to current models of IGF2 imprinting and the hypothesized conflict of parental reproductive interests which bears on the phenomenon of pa rental imprinting. (C) 1995 Wiley-Liss, Inc.