AUTHOR=Paylar Berkay , Pramanik Subrata , Bezabhe Yared H. , Olsson Per-Erik 

TITLE=Temporal sex specific brain gene expression pattern during early rat embryonic development

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=12

YEAR=2024

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2024.1343800

DOI=10.3389/fcell.2024.1343800

ISSN=2296-634X

ABSTRACT=<p><bold>Background:</bold> The classical concept of brain sex differentiation suggests that steroid hormones released from the gonads program male and female brains differently. However, several studies indicate that steroid hormones are not the only determinant of brain sex differentiation and that genetic differences could also be involved. </p><p><bold>Methods:</bold> In this study, we have performed RNA sequencing of rat brains at embryonic days 12 (E12), E13, and E14. The aim was to identify differentially expressed genes between male and female rat brains during early development.</p><p><bold>Results:</bold> Analysis of genes expressed with the highest sex differences showed that <italic>Xist</italic> was highly expressed in females having XX genotype with an increasing expression over time. Analysis of genes expressed with the highest male expression identified three early genes, <italic>Sry2, Eif2s3y</italic>, and <italic>Ddx3y</italic>.</p><p><bold>Discussion:</bold> The observed sex-specific expression of genes at early development confirms that the rat brain is sexually dimorphic prior to gonadal action on the brain and identifies <italic>Sry2</italic> and <italic>Eif2s3y</italic> as early genes contributing to male brain development.</p>