Endogenous retrovirus control of calbindin is essential for human early embryogenesis.

HERVH integration on chromosome 8q21.3 is essential for human embryonic development, regulating CALB1 expression critical for ESC growth and early embryo formation.

• Why it matters: Understanding how endogenous retroviruses influence human development can reveal fundamental mechanisms and potential links to diseases like cancer, where HERV regulation is disrupted.
• What they did: The study analyzed HERVH and CALB1 expression in preimplantation embryos and ESCs, demonstrating that HERVH integration during evolution coincides with CALB1 activation necessary for embryogenesis.
• The result: Findings show CALB1 expression, driven by HERVH, is vital for ESC proliferation, preventing senescence, and forming early embryonic structures, highlighting HERVs' role in human development.