Y chromosomal fertility genes in Drosophila

In Drosophila, as in many other organisms, the Y chromosome usually appears heterochromatic and only few genes have been discovered. The known genes are essentially for male fertility but their function is unknown. They appear not to code for proteins although this cannot yet be entirely excluded. As an alternative function, protein binding to the growing transcripts is considered, which may be important in the context of nuclear domain formation.