Fig. 1

Sample information and miRNA expression distribution. a Schematic illustration of sample numbers according to population ID and newborn sex. The abbreviations here and in the text indicate: A – African Americans; E – European Americans; S – South Asians; X – East Asians; F - female newborn and M - male newborn. b Violin plot showing miRNA expression distribution. Y-axis shows the quantile normalized log2-transformed miRNA read count values after removing the batch effect. X-axis labels indicate 938 annotated miRNAs (Known), 127 annotated miRNAs differentially expressed among populations (Known DE), 70 novel miRNAs (Novel), and 12 novel miRNAs differentially expressed among populations (Novel DE). c Percentage of total expression variance explained by newborn sex and population. Bars represents the mean variation explained by the categorical trait. Error bars represent the standard deviation of the mean. d-g Principal component analysis plots based on the miRNA expression of all 1008 miRNAs (d, colored according to population and f, colored according to newborn sex), 139 miRNAs differentially expressed among populations (e), and 32 miRNAs differentially expressed depending on the sex of the newborn (g)