Figure 6. Genome-wide RAD51 values in males and females.

RAD51 foci were used as a surrogate for DSBs and the number of foci in leptotene stage cells determined [44 cells from 3 males (white triangles) and 39 cells from 5 females (black circles)]. The male and female distributions were virtually non-overlapping, with almost all spermatocytes exhibiting fewer than 200 RAD51 foci and most oocytes more than 200 foci. Further, the mean number of RAD51 foci (± S.E.) was significantly lower in males than in females (134.07 ± 5.47 and 250.28 ± 10.21, respectively; t=10.4; p<0.0001).