Figure 2. Early meiotic defects in TBP-associated factor 7l/testis-expressed gene 11 (Taf7l Tex11) double-mutant male mice. Surface spread analysis was performed on spermatocytes from adult (2-month-old) mice of 4 genotypes: wild type, Taf7l^–/Y Tex11^–/Y and Taf7l^–/Y Tex11^–/Y double mutant. Spread spermatocyte nuclei were immunostained with antibodies against component of synaptonemal complex central element (SYCP1) and component of synaptonemal complex lateral elements (SYCP2), as described previously (Yang et al, 2006). Three mice per genotype were analyzed. At least 100 spermatocytes from each mouse were scored and were categorized into leptotene, zygotene, pachytene, diplotene, and diakinesis/metaphase spermatocytes, according to the immunostaining patterns of SYCP1 and SYCP2. Pachytene spermatocytes were further divided into synapsed (all chromosomes were synapsed) and unsynapsed (some chromosomes were unsynapsed). The percentage of each category of spermatocytes (average ± SD) was plotted. Asterisk indicates values were statistically significant in comparison with wild type or other genotypes (P < .05) by Student's t test.