While the genomes present in our somatic cells inevitably disappear upon death, our germ cells can pass on our genes to, in principal, endless generations of offspring. For this reason genome integritity maintenance is differentially regulated in the germline, which includes the preimplantation embryonic stem cells. 

The work of Geert Hamer focusses on genome stability maintenance and development of germ cells and human preimplantation embryos. For instance, he and co-workers unravelled the mechanisms that lead to meiotic arrest during human spermatogenesis and recently discovered a miRNA that is specifically secreted by, and aids implantation of, good quality (euploid) human embryos. In addition, one of Geert Hamer's students succeeded to induce spermatogonial differentiation and meiosis in vitro, a technique that is currently explored in many laboratories for fertilty treatment or preservation. However, current results show that meiotic checkpoints, normally required to prevent genomic instability and aneuploidies to be transmitted to the offspring, are not necessarily active in vitro. In vitro generated spermatid-like cells should thus be thoroughly investigated before being considered for clinical use. 

Geert Hamer and colleagues were the first the publish the transcriptome of human male germ cells. This study formed the basis of a novel research line that focusses on the role germ cell-specific genes in the development and treatment of cancer. For this research he recently won the prestigious Snoo-award for developmental biology and an Amsterdam Reproduction & Development (AR&D) research grant. 

https://orcid.org/0000-0002-9583-6796