A geneticist is using a three-point testeross to map three linked Drosophila recessive mutations called a, b, and c, where a is associated with anomalous gait, b is associated with buckled wings, and c is associated with curved bristles. She first crosses homozygous anomalous, buckled flies to homozygous curved flies. Next, she testcrosses the Fi progeny to anomalous, buckled, curved flies. She obtains 1000 progeny distributed as shown. From this data, calculate the map distance between b and c. Testcross progeny phenotype Number map distance: m. u. curved 281 anomalous, buckled 279 wild type anamalous, buckled, curved buckled, curved 133 anomalous 127 86 anomalous, curved buckled 84

In c. elegans, genetics model organism, movement problems (unc) and small body size (sma) are encoded by two mutant alleles that are recessive to those that produce wild-type traits (unc+ and sma+). A worm homozygous for movement problems and small body is crossed with a worm homozygous for the wild-type traits. The F1 have normal movement and normal body size. The F1 are then crossed with worms that have movement problems and small body size in a testcross. The progeny of this testcross is: Normal movement, normal body size            210 Movement problems, normal body size          9 Normal movement, small body size                 11 Movement problems, small body size           193   a)From the test cross results, can you tell if the two genes are on the same chromosome or not? Explain your reasoning.   b)What phenotypic proportions would be expected if the genes for round eyes and white body were located on different chromosomes?  (please explain hot to get to these conclusions)

In Drosophila, a heterozygous female for the X-linkedrecessive traits a, b, and c was crossed to a male that phenotypically expressed a, b, and c. The offspring occurred inthe following phenotypic ratios.+  b  c                            460a  +  +                           450a  b  c                              32+ + +                              38a  + c                              11+ b +                               9 No other phenotypes were observed.(a) What is the genotypic arrangement of the alleles ofthese genes on the X chromosome of the female?

You are working with a hypothetical fly and have found color and wing mutants. Preliminary work indicates that the mutant traits are recessive and the associated genes are not sex-linked, but beyond that, you have no information. You first look at 2 genes, each with 2 alleles. "B" or “b" for body color and "W" or "w" for wing surface. The red-body phenotype is dominant to the yellow-body phenotype and smooth wings are dominant to crinkled wings.

In mice, coat color is due to the inheritance of three genes located on three different chromosomes.  The A gene which determine if a yellow band is present on the hair     ( A_= yellow band, aa= no yellow band ) and the B gene which determines if the hair is brown ( bb ) or Black ( B_).  The A and B genes interact to produce the following coat colors: Agouti:     A_B_ Cinnamon:  A_bb black:       aaB_ brown      aabb The third gene is the C gene, which determines if the mice has any hair pigment at all.  If the mouse has at least one C allele then the coat color will be determined by the A and B genes as described above.  However, if the mouse is cc in genotype it will be albino, regardless of the mouse’s A and B genotype. 1.If a AabbCc mouse mates with a aaBbcc mouse, what is the probability that the mouse will be born brown? (a) ½    (b) ¼  (c) 1/8   (d) 1/16   (e) none of the above

Two Drosophila flies that had normal (transparent, long) wings were mated. In the progeny, two new phenotypes appeared, dusky wings (having a semi-opaque appearance) and clipped wings (with squared ends). The progeny were as follows: Females: 179 transparent, long 58 transparent, clipped Males: 92 transparent, long 89 dusky, long 28 transparent, clipped 31 dusky, clipped a) Provide a genetic explanation for these results, showing genotypes of parents and of all progeny classes under your model. b) Design a test for your model.

There are two genetic disorders that result from mutation in imprinted genes: Prader-Willi syndrome, Angelman syndrome.  Angelman syndrome results from deletion of UBE3A, which is a gene imprinted such that only the maternal copy is expressed. In the pedigree above, individual I-1 is heterozygous for a deletion of UBE3A and does not have Angelman syndrome.  Individual I-2 is homozygous wild type for UBE3A.  Which individuals in the pedigree are at risk for exhibiting Angelman syndrome, if any?  (Who could potentially have the syndrome, based on what alleles it is possible for them to inherit and express?)   Question 8 options:   Only I-1 could have been at risk.  If he does not have the syndrome, no one in the pedigree could.   Only III-1 is at risk   I-1, II-2, and III-1 are all at risk   Only II-2 is at risk   No one in the pedigree is at risk   Both II-2 and III-1 are at…

Suppose researchers identified two Drosophila melanogaster mutant phenotypes. One phenotype is called maniac and the other is called shiny. In order to determine the mode of inheritance of the mutant allele responsible for each phenotype, males that have both mutant phenotypes are mated with wild-type (wt) females to produce F₁ progeny. Then, the F₁ progeny are mated together and the F2 progeny are scored. F₁ phenotypic class maniac male maniac female n 481 478 autosomal dominant for maniac and X-linked dominant for shiny autosomal recessive for maniac and autosomal recessive for shiny autosomal dominant for maniac and X-linked recessive for shiny X-linked dominant for maniac and X-linked recessive for shiny What is the genotype of the original male parent? F2 phenotypic class maniac female maniac male What is the mode of inheritance for the genes controlling maniac and shiny? maniac, shiny male shiny male wt female wt male homozygous mutant at both loci heterozygous mutant at one…

The data set attached presents the results of a testcross using female flies heterozygous for three traits and male flies, which are homozygous recessive. For simplicity, mutant alleles are shown with letters a, b, and c and wildtype alleles are indicated by a “+” symbol. For this part of the report do the following in order: a) Determine the gene order (which gene is in the middle?)d) Construct a genetic map for the three genes, including the map distances between them. Clearly indicate the logic you followed and show all your calculations. Include the full distance calculations for the two most distanced genes (do not just add the other 2 distances).  Ensure the work is neat and clear and does not contain spelling or grammatical errors so that it is understandable. Make sure to double check the solution provided.

In a mutant screen in Drosophila, you identified a gene related to memory, as evidenced by the inability of recessive homozygotes to learn to associate a particular scent with the availability of food. Given another line of flies with an autosomal mutation that produces orange eyes, design a series of crosses to determine the map distance between these two loci. You do not need to calculate recombination frequency.