Drosphilia Protocol

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Drosphilia Protocol Observations and Procedure: My double mutant flies are white eyed and have vestigial wings in comparison to the wild type flies. I plan on determining how these traits are transmitted through genes is as follows: Step One: Parental Generation I obtained a total of ten double mutant virgin females from my stock vial by clearing out all the adults and capturing all the newly hatched females. I put all three virgin females in a separate vial with six wild type males. All, except one, female died within the week with most of my wild type males flies. I was still able to keep the rest alive and larvae had been produced about a week later.

P Generation: Females Males Phenotype White eyes Wild Type Vestigial Wings Genotype Unknown Unknown Step Two: F1 Generation Ten days after my original cross between the double mutant virgin female flies and the male wild type flies, my F1 generation began to emerge.

My totals and observations are as follows: F1 Generation: Females Males Phenotype Wild Type White Eyes Long Wings Possible Genotype Xw+vg X Xwvg Y Total # Collected Ratios of Phenotypes 1:1 Xw "³ White eye, X-linked recessive allele Xvg "³ Vestigial wings, Autosomal Recessive Allele Xwvg "³ White eyes, vestigial wings, X-linked recessive, Autosomal recessive alleles Xw+ "³ Wild type allele Y "³ No alleles for X-linked traits are carried on the Y chromosome Punnett Squares Xwvg Xwvg X++ Xwvg X++ Xwvg X++ Y Xwvg Y Xwvg Y Based on my observations of the F1 Generation, the phenotypes and genotypes of the Parental Generation are likely to be: Parental Generation : Females Males Phenotype White eyes Wild Type Vestigial Wings Genotype Xwvg Xwvg X++ Y The white eyes are found only in the males in the F1 generation, while the vestigial wings did not show up in the males of the F1 generation. All of my females in the F1 generation ended up being wild type. I believe that the white eyes are a X-linked recessive trait while the vestigial wings are an autosomal recessive trait. My next cross will be between the F1 females and the F1 males. I can observe the traits in the F2 geneartion to prove or disprove my hypothesis.

Step 3: F2 Generation: As of now, I have done a F1 x F1 cross with no F2 emergence, so the following information I anticipate to occur regarding my F2 generation. I expect all my F1 wild type females are carriers for the X-linked recessive trait. Therefore crossing them with my F1 males should yield the following results: F2 Generation Female Male Phenotype Wild Type Wild Type Genotype Xw+vg Xwvg Xw+vg Y Total 50% of females 50% of males Punnett Squares Xw+vg Xwvg Xw+vg Xw+vg Xw+vg Y Xw+vg Y Xw+vg Y Plan for Next Step: Based on the results of my F1 generation and F2 generation, I would be done with my crosses. I would want to obtain a large number of F2 generation specimens to increase my accuracy when I do my Chi square test. I will be able to to determine whether or not the traits of my flies are closely linked on the X chromosome. If they are closely linked, I will be able to determine a map based on the frequency of recombinants. My final report would include all the data and calculations in this report.