GSE184860
High-throughput small RNA sequencing of the human placenta at first and third trimester with fetal sex differences analysis
Human placenta bulk small RNA-seq from healthy pregnancies without infertility, from n=113 first trimester (58 female, 55 male) and n=47 third trimester (19 female, 28 male) tissue samples. Tissue was collected at Cedars-Sinai Medical Center in Los Angeles, California, USA. First trimester placenta was collected at 70-102 days of gestation from leftover chorionic villus sampling for prenatal genetic diagnosis. Third trimester placenta was collected after delivery at 254-290 days gestation from the fetal side near the umbilical cord insertion site beneath the amnion. Mothers with pre-existing diabetes or hypertension were excluded. All pregnancies were conceived without fertility treatments, were normal karyotype, and resulted in live singleton births. The average parental age was advanced (over 35 years old) but PCA analysis did not show clustering by either maternal or paternal age. Gonzalez et al 2021 [PMID: 34030457] analyzes similarities and differences between first and third trimester miRNA expression overall. Flowers et al 2021 focuses on the effect of fetal sex on miRNA expression across gestation. Overall design: Small RNAs from human placenta were sequenced. Differential expression analysis was performed on miRNAs with the R package DESeq2 and two sample variables (trimester and fetal sex).