TABLE 3

Test for chromatid interference in adjacent intervals

IntervalsStrainTwo strandsThree strandsFour strandsP valuea
ADE2SER1HIS3 MSH4 182270.27
ADE2SER1HIS3 msh4 81050.76
HIS4CEN3MAT MSH4 4173360.90
HIS4CEN3MAT msh4 1350220.27
CAN1URA3HOM3 MSH4 74153730.97
CAN1URA3HOM3 msh4 3452340.59

For the pairs of adjacent intervals indicated, all tetrads that were tetratype in both intervals were classified as two-strand, three-strand, or four-strand double crossovers according to the number of chromatids involved.

  • a Probability, based on a chi-square test, that the ratio of two-, three-, and four-strand double crossovers observed is consistent with the 1:2:1 ratio expected in the absence of chromatid interference.