Global Gene Expression in the Human Fetal Testis and Ovary1

Abstract

This study describes a temporal profile of gene expression from normal human fetal testes and ovaries. Gonads from 34 fetuses between 9 wk and 20 wk of gestation were obtained from the Department of Pathology and the Birth Defects Research Laboratory at the University of Washington. Relative transcript levels were determined using the Affymetrix Human Genome U133A Plus 2.0 arrays. Sex determination occurs in the human gonad at approximately 6 wk of gestation with development of the testis driven by expression of SRY. In this study, SRY transcript was present and elevated at 9 wk of gestation in the testis but was absent in the ovary. The transcript levels of other testis-specific factors SOX9 and AMH and the steroidogenic genes CYP17A1, CYP11A1, STAR, and HSD17B3 were all significantly higher in the testis. In contrast, transcripts known to be involved in meiosis, including STRA8, SPO11, SYCP3, TEX11, TEX14, and STAG3, showed highest expression in the fetal ovary beginning at Week 12. These gene expression profiles will be a resource for understanding and defining normal gonad development and provide the opportunity to dissect abnormal development.

Regulation of meiotic entry and gonadal sex differentiation in the human: normal and disrupted signaling

“…The expression of STRA8 is followed by upregulation of SCP3, SPO11, and DMC1, which are markers of meiotic progression. In accordance with this general notion, expression of SCP3 was detected in ovaries from 44) and DMC1 from GW 13 (5,42). In addition, SPO11 and SCP1 expression was detected from GW 13 in human fetal ovaries (5,44).…”

“…This was recently confirmed by the presence of γH2AX-positive (marks double-strand breaks) oogonia at GW 10 (5) and SCP3-positive oogonia from GW 12-14 (42,43). The pre-meiosis marker STRA8 was expressed before and around this developmental time point (5,6,37,44), with low transcript levels of STRA8 detectable from GW 8-9 (6,44). The expression of STRA8 in fetal ovaries peaks around GW 12-14 but remains until GW 18-20 (5,6,44).…”

“…The pre-meiosis marker STRA8 was expressed before and around this developmental time point (5,6,37,44), with low transcript levels of STRA8 detectable from GW 8-9 (6,44). The expression of STRA8 in fetal ovaries peaks around GW 12-14 but remains until GW 18-20 (5,6,44). In contrast to fetal ovaries, STRA8 expression was not detected in human fetal testes (6,42,44).…”

“…The expression of STRA8 in fetal ovaries peaks around GW 12-14 but remains until GW 18-20 (5,6,44). In contrast to fetal ovaries, STRA8 expression was not detected in human fetal testes (6,42,44). The expression of STRA8 is followed by upregulation of SCP3, SPO11, and DMC1, which are markers of meiotic progression.…”

Screening of genes involved in chromosome segregation during meiosis I: in vitro gene transfer to mouse fetal oocytes

“…[20][21][22][23] Although gene expression profile data for fetal or neonatal ovaries have been provided in mouse and human, and have enabled the analysis of genes involved in the initiation of meiosis, the sex differentiation of the gonad, early meiosis, and ovarian and follicle development, investigations of meiotic prophase I have been lacking. [24][25][26][27][28] In yeast, it is estimated that B150 genes may be meiosis-specific. 29,30 In our current study, we screened 99 genes that are upregulated during prophase in meiosis I.…”