Members of the CDY family have different expression patterns: CDY1 transcripts have the best correlation with complete spermatogenesis.
Kleiman SE, Yogev L, Hauser R, Botchan A, Bar-Shira Maymon B, Schreiber L, Paz G, Yavetz H. Hum Genet. 2003 Nov; 113(6):486-92. Epub 2003 Sep 3.