In Japan, the prevalence of low birth weight (< 2,500 g) has been increasing, probably owing to leanness, exposure to toxic chemicals and smoking. Epidemiological studies revealed that low birth weight poses risks of hypertension, coronary heart diseases and diabetes. Although the precise mechanism has not been understood, there is an urgent need for appropriate public health interventions. MicroRNA (miRNA) is a small RNA consisting of approximately 22 nucleotides and distributed in a wide variety of organs and body fluids. miRNAs are involved in the pathogenesis of various human diseases and expected to be their potential biomarkers. The interest on the study on miRNA in the research field of developmental origins of health and disease (DOHaD) has been growing, and the number of related papers has been increasing. There are several molecular epidemiological studies on the relationship between maternal miRNA and fetal development. The effects of smoking and dietary factors on miRNA expression and fetal development have been investigated in epidemiological and experimental studies. However, the role of maternal miRNA in fetal development has not been well understood so far. In this review, the current status of studies on miRNA expression in DOHaD research is described and future perspectives are discussed.
