Table 1.
Quantitation of pairing between meiotic chromosomes in Msh4−/−, Msh5−/−, and Msh4−/−/Msh5−/−spermatocytes
|
|
Msh4+/+
|
Msh4−/−
|
Msh5−/−
|
Msh4−/−/Msh5−/−
|
|---|---|---|---|---|
| Percent nuclei with 100% pairing | 64.9a | 0 | 0 | 0 |
| (48/74) | ||||
| Percent nuclei with no pairing | 9.4b | 31 | 90 | 92 |
| (7/74) | (18/58) | (54/60) | (46/50) | |
| Percent nuclei with partial pairing | 25.7c | 69 | 10 | 8 |
| (19/74) | (40/58) | (6/60) | (4/50) | |
| Analysis of partially paired chromosomesd | ||||
| Percent nonpaired chromosomes | 0 | 86.0 | 89.6 | 90.6 |
| (0/760) | (1376/1600) | (251/240) | (145/160) | |
| Percent homologous partial pairing | 100 | 7.1 | 6.25 | 0 |
| (760/760) | (114/1600) | (15/240) | (0/160) | |
| Percent homologous pairing | 0 | 6.9 | 4.2 | 9.4 |
| (110/1600) | (10/240) | (15/160) | ||
| Statistical analysis of pairing trends between genotypese | ||||
| χ2 comparison with Msh4−/− | P < 0.0001 | — | P < 0.0001 | P < 0.0001 |
| χ2 comparison with Msh5−/− | P < 0.0001 | P < 0.0001 | — | N.S. (P = 0.09) |
Values are percent, with number values in parentheses.
a
Nuclei at pachynema.
b
Nuclei at leptonema.
c
Nuclei at zygonema (with all chromosomes being partially paired).
d
Total numbers of chromosomes are obtained by multiplying 40 (total number of chromosomes per cell) by the number of nuclei showing some pairing.
e
Chi-square analyses were performed between different pairs of groups. (N.S.) Not significant.