Mutation analysis of the growth factor genes PlGF, Flt1, IGF-I, and IGF-IR in intrauterine growth restriction with abnormal placental blood flow

Objective. The objective of our study was to investigate a possible role of pathogenic mutations in the growth factor genes insulin like growth factor I (IGF-I) and placental growth factor (PlGF) and their receptors IGF-IR and fins-like tyrosine kinase 1 (Flt1) in the pathogenesis of placental dysfunction. Methods. We analyzed two patient groups with IUGR (intrauterine growth restriction), 18 mother-child pairs with absent or reversed enddiastolic flow (ARED) in the umbilical artery and 12 mother-child pairs with preserved enddiastolic flow (PED) in the presence of a bilateral abnormal uterine artery Doppler waveform (Notching). The control group comprised of 50 healthy mother-child pairs. Results. Sequencing did not show a pathogenic mutation in any of the analyzed genes. However, we detected three novel polymorphisms in the IGF-IR gene. In addition, we identified one unknown polymorphism in exon 1 of the non-coding region of PlGF and 2 novel variants in exons 1 and 6 of Flt1. Conclusion. In summary, our results do not provide evidence for a relevant role of pathogenic mutations in the genes IGF-I, IGF-IR, PlGF, and Flt1 in the etiology of IUGR with ARED or PED flow.