miRNA profiles in muscle of IUGR and normal weight pig fetuses

Intrauterine growth restriction (IUGR) is a leading cause of neonatal morbidity and mortality in humans and domestic animals. Developmental adaptations of skeletal muscle in IUGR lead to increased risk of premature muscle loss and metabolic disease later during life. Although transcriptome-wide profiles in muscle associated with IUGR have been reported, their regulation by miRNAs is not well understood. The aim of this study was to identify differences in miRNA expression in porcine skeletal muscle of IUGR and normal-weight (NW) littermates during late foetal development (day 90 of gestation). Overall design: RNA sequencing was performed on a total of 8 semitendinous muscle samples collected from 4 pig litters at day 90 of gestation. Two male fetuses were collected from each litter, one with normal weight as defined by weight above the litter average (Large) and a IUGR fetus with weight >2 SD below the average litter weight (Small). Differentially expressed genes were identified from analyses taking account of 'litter'.