The GINS complex plays an essential role in the initiation of DNA replication, and progression of DNA replication forks. GINS complex seems to bind preferentially to single-stranded DNA. Component of the GINS complex which is a heterotetramer of GINS1, GINS2, GINS3 and GINS4. Forms a stable subcomplex with GINS2. GINS complex interacts with DNA primase in vitro (By similarity). Component of the CMG helicase complex, composed of the MCM2-7 complex, the GINS complex and CDC45 (By similarity). Associates with chromatin. Belongs to the GINS3/PSF3 family.