P –154 The role of the X Chromosome in early human embryo metabolism

This study is a reanalysis of publicly available RNA-seq data, including 1176 single cells from 59 blastocysts (24 E5, 18 E6, 17 E7) published in one study (Petropoulos et al 2016).Participants/materials, setting, methodsCells were subjected to a digital karyotype inference algorithm and aneuploid samples were removed from the dataset. Sex differential gene expression analyses (DE) were then performed in euploid trophectoderm cells (TE; 233 XY from 16 embryos and 180 XX cells from 12 embryos). Cell numbers from ICM were too sparse to compare.Main results and the role of chanceAnalysis of XX and XY TE revealed 618 significantly differentially expressed genes (DEGs; 507 upregulated in XX cells, and 111 upregulated in XY cells). These genes are spread across autosomes and sex chromosomes. Interestingly, G6PD is not significantly more highly expressed in XX cells.Gene Ontology (GO) analysis of the XX-biased DEGs revealed a transcriptional sex bias in metabolism-related GO categories, including “mitochondrial ATP synthesis coupled electron transport”, and “respiratory chain complex I”.Gene-level assessment revealed that the drivers of these enrichments are spread across the genome, but 28/64 reside on Chromosome X (hypergeometric p-value = 5.984473e–27), including NDUFA1, NDUFB11 , and COX7B (components of the electron transport chain), and SLC25A5 (an ATP/ADP transporter involved in maintaining mitochondrial membrane potential). This indicates a direct role for multiple...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research