An Aspergillus diploid is +++/profpa paba, in which pro is a recessive allele for proline requirement, fpa is a recessive allele for fluorophenylalanine resistance, and paba is a recessive allele for para-aminobenzoic acid (paba) requirement. By plating asexual spores on fluorophenylalanine, selection for resistant colonies can be made. Of 154 DIPLOID resistant colonies, 35 require neither proline nor paba, 110 require paba, and 9 require both.
(a) What do these figures tell you?
(b) Sketch your conclusions in the form of a map.
(c) Some resistant colonies (not the ones described) are haploid. What would you predict their genotype to be?
These areas are emphasized.
(a) The results indicate a linkage of pro and paba to fpa, and their different frequencies reflect the ...
Techniques of eukaryotic chromosome mapping are included. The conclusion is sketched for the figures. Recessive alleles for proline requirements are given.