Transcriptome profiles for defining avian primordial germ cell development

Avian biology has contributed to many research areas, such as sustainable protein production, endocrinology, developmental biology, neurosciences, and immunology. Primordial germ cells, lineage-restricted stem cells, are key for the conservation of genetic diversity of bird species, as well as for studying germ cell development and producing genetic models to study avian biology. Here, we review the current knowledge of developmental and fate decision processes in avian primordial germ cells focusing on insights revealed by gene expression profiling. We summarized the characteristics and fundamental pathways required for chicken primordial cell growth. In addition, we discuss the common and disparate features of PGCs from chicken compared to other avian species. These insights are valuable for researchers in germ cell biology, reproductive biotechnology, and avian genetic conservation and indicate a need for the analysis of further bird species.