Specific organization of genes in relation to the sperm nuclear matrix.

We have recently reported that mammalian sperm DNA, the most highly condensed and functionally inert eukaryotic DNA, is organized into DNA loop domains attached at their bases to a sperm nuclear matrix (Chromosoma, 98: 153, 1989). We report here the specific arrangement of genes within the sperm loop domains by measuring the proximity of six hamster genes to the sperm nuclear matrix. After restriction endonuclease treatment of sperm nuclear matrices, five genes were clearly not associated with the sperm nuclear matrix and only one, alpha A-crystallin, was within 2 Kb of the matrix. This suggests that sperm DNA is organized in a specific manner in relation to the sperm matrix.