biostudies-literatureChitiashvili TNICHD NIH HHSHoward Hughes Medical InstituteNCI NIH HHSNIGMS NIH HHS1268-1278https://www.ebi.ac.uk/biostudies/studies/S-EPMC9214056biostudies-literatureUnknown17(6)Human germ cell development is a highly regulated process beginning soon after embryo implantation with the specification of primordial germ cells (PGCs) and ending in adulthood with the differentiation of gametes. Here, we show that fibroblast growth factor receptor 3 (FGFR3) is expressed by human PGCs during the first and second trimester, becoming repressed as PGCs differentiate into primordial oocytes. Using fluorescence-activated cell sorting (FACS) with antibodies that recognize FGFR3 followed by single-cell RNA sequencing, we show that isolating FGFR3-positive cells enriches for human PGCs. Taken together, FGFR3 could be used in future studies as a strategy to identify maturing PGCs in vitro.Stem cell reportsFGFR3 is expressed by human primordial germ cells and is repressed after meiotic initiation to form primordial oocytes.PMC9214056P30 CA016042R01 HD079546R24 HD000836R01 HD098387P01 GM099134Chitiashvili THsu FMClark ADror IPlath KfalseFGFR3 is expressed by human primordial germ cells and is repressed after meiotic initiation to form primordial oocytes.Human germ cell development is a highly regulated process beginning soon after embryo implantation with the specification of primordial germ cells (PGCs) and ending in adulthood with the differentiation of gametes. Here, we show that fibroblast growth factor receptor 3 (FGFR3) is expressed by human PGCs during the first and second trimester, becoming repressed as PGCs differentiate into primordial oocytes. Using fluorescence-activated cell sorting (FACS) with antibodies that recognize FGFR3 followed by single-cell RNA sequencing, we show that isolating FGFR3-positive cells enriches for human PGCs. Taken together, FGFR3 could be used in future studies as a strategy to identify maturing PGCs in vitro.2022-01-01T00:00:00Z2022 Jun2026-05-27T20:29:08.67Z2025-02-19T02:43:51.4ZS-EPMC92140563559486010.1016/j.stemcr.2022.04.015