MCM5 is a component of the MCM2-7 complex (MCM complex), a replicative helicase essential for 'once per cell cycle' DNA replication initiation and elongation in eukaryotic cells. It is thought to function in cell cycle regulation and has increased expression in the transition from the G0 to the G1/S phase. It interacts with MCM2, MCM3, MCM7 and STAT1. Variants in MCM5 that result in dysfunctional protein are associated with Meier-Gorlin syndrome (MGORS), described by dwarfism, microtia and patellar aplasia and hypoplasia. In immunohistochemistry of normal tissue, MCM5 has nuclear positivity in hematopoietic cells, cytotrophoblastic cells in the placenta, immune cells, the testes, and at low to moderate levels in other tissues throughout the body. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804; Eur J Hum Genet 25, 646–650 (2017), DOI:10.1038/ejhg.2017.5