Drosophila has four pairs of chromosomes: the sex chromosomes (XX in the females; XY in the males) and three pairs of autosomes. You are studying a new mutant strain with blue eyes. You wish to know if blue eye colour is a dominant mutation and on which chromosome the blue eye locus can be found. When you cross a pure-breeding female blue-eyed fly with vestigial wings and spineless bristles to a male fly with wild type eye colour, wings, and bristles, all of the F1 progeny are completely wild type. An F1 male is backcrossed to a triple mutant female, producing the following progeny (remember that there is no crossing over in Drosophila males):
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Wild type eyes, wings, and bristles:
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72 females, 69 males
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Wild type eyes and bristles, vestigial:
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83 females, 77 males
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Wild type wings, blue eyes, spineless:
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60 females, 65 males
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Blue eyes, spineless, vestigial:
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62 females, 58 males
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When an F1 female is backcrossed to a triple mutant male, the following 1,000 progeny are produced:
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Wild type eyes, wings, and bristles:
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90 females, 89 males
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Wild type eyes and bristles, vestigial:
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83 females, 98 males
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Wild type eyes and wings, spineless:
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37 females, 35 males
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Wild type wings and bristles, blue eyes:
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36 females, 34 males
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Wild type wings, blue eyes, spineless:
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92 females, 88 males
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Wild type eyes, spineless, vestigial:
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34 females, 39 males
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Wild type bristles, vestigial, blue eyes:
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33 females, 37 males
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Blue eyes, spineless, vestigial:
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90 females, 85 males
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Calculate the map distance between blue eye and any linked genes. Show your work.