MAPPING OF THE HOMOTHALLIC GENES, HMa AND HMa, IN SACCHAROMYCES YEASTS
نویسندگان
چکیده
Two of the three homothallic genes, HMa and HMa, showed direct linkage to the mating-type locus at approximately 73 and 98 stranes (57 and 65 centimorgans [cM]), respectively, whereas, the other, HO, showed no linkage to 25 standard markers distributed over 17 chromosomes including the matingtype locus. To determine whether the HMa and HMa loci located on the left or right side of the mating-type locus, equations for three factor analysis of three linked genes were derived. Tetrad data were collected and were compared with expected values by x* statistics. Calculations indicated that the HMsv gene is probably located on the right arm at 95 stranes (65 cM) from the centromere and the HMa locus at approximately 90 stranes (64 cM) on the left arm of chromosome ZZZ.
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