This gene belongs to the VCX/Y gene family, which has multiple members on both X and Y chromosomes that are expressed exclusively in male germ cells. The VCX gene cluster is polymorphic in terms of copy number; different individuals may have a different number of VCX genes. This gene contains two copies of a 30 nt tandem repeat. Deletion of a nearby member of this family was implicated in mental retardation. [provided by RefSeq, Feb 2015].