Dihybrid Cross Lab Report

• Use these data to construct a map of these three genes in two steps.

For one of the monohybrid crosses you performed in this Investigation, describe how to use the phenotype ratios to determine

Draw a schematic of the vector and include all of the genetic loci that will permit this two-gene vector to function as a shuttle vector between human cells and E.coli cells. (For your convenience, I have put the A and B polypeptide coding regions on the two-gene vector schematic.)

Part A: To construct a mapping cross of linked genes, it is important that the genotypes of

There were eight different phenotypes among the progeny. The highest phenotypic frequency was the w+m+f+ at 40% of the progeny. The lowest was the w+mf+ with only 2 % of the progeny (Table 3). The sum of the recombinant frequencies between genes, table 4, was used to determine the gene distance. The recombinant frequency was determined by counting the number of individuals whose genes differed from that of the parental type. For example, how many individuals white eye gene, and miniature wing gene, differed from both wild-type or both mutants. Recombination occurred between the white and miniature gene 33 times. Recombination occurred between the miniature and the forked genes 31 times. Recombination occurred between the white and forked genes 44 time. Double recombination occurred 10 times. Therefore, genes w and f are 64 m.u. apart, m and w are 33 m.u. apart, and m and f are 31 m.u. apart (Figure

The markers showing linkage are markers B, C, and D since they are more prevalent and highly associated with the mutant allele.

FLPTer have been used to quantify the marker gene movement and evolution in strain 1 to strain 4

Figure 1 Gel Electrophoresis for Replication Taster PTC. The gel is composed of an ethidium bromide stained 3% agarose gel demonstrating DNA fragments which were a depiction of PCR amplification. The agarose gel contains nine loading samples, including from left to right, the MW marker lane 1 precision mol mass standard, lane 2 TB undigested PTC (5µl of DNA, 5µl of master mix P, and 2.5µl of loading dye), lane 3 TB digested PTC (5µl of DNA, 5µl of master mix P, 2µl Fnu4HI, and 3µl of loading dye), lane 4 TB A(L)DH G (10µl DNA, 10µl master mix G, and 5µl loading dye), lane 5 TB A(L)DH A (10µl DNA, 10µl master mix A, and 5µl loading dye), lane 6 MG undigested PTC (5µl of DNA, 5µl of master mix P, and 2.5µl of loading dye), lane 7 MG digested PTC (5µl of DNA, 5µl of master mix P, 2µl Fnu4HI, and 3µl of loading dye), lane 8 MG A(L)DH G (10µl DNA, 10µl master mix G, and 5µl loading dye), lane 9 MG A(L)DH A (10µl DNA, 10µl master mix A, and 5µl loading dye).

The distances between the centromeres and genes were determined. Refer to results section for exact distances for each gene. The distance or location is a significant because it can affect the frequency of crossing over and thus recombination. The results of this crossing further determine if recombination occurred in Sordaria. Recombination is important because it is an indication of the genes joining together to form new combinations; increasing genetic variation/diversity. The results encountered (according to percentage error) indicate that recombination did not occur in high quantities. The data collected experimentally (my own group) resulted with a 60% recombinant rate concerning the wildtype and tan crossing. The wildtype and grey crossing resulted with a 52% recombinant rate. The arrangement most encountered was a 2+: 2t: 2+: 2t, meaning a crossover between the gene and centromere did occur in the second division of meiosis II (recombinant chromatids). Another common arrangement encountered were the asci having a pattern of 6:2 and one 5:3 arrangement due to the genes undergoing gene conversion.


Bloom's Level: 1. Remember
Learning Outcome: 06.01.03 Predict the outcome of crosses involving genetic variation in chloroplast genomes.
Section: 06.01
Topic: Extranuclear Inheritance: Chloroplasts

The progeny of this cross were known at the F1 generation. Phenotypes seen in this cross were recorded. Males from this cross were collected. A male that with a different phenotype from the mutation in the mutant flies was selected. (If the mutation in the mutant flies is white-eye, a male without an eye mutation is selected.) The selected male from the F1 generation is then crossed with a virgin female from the parental generation. After which, the phenotypes seen were recorded and used to determine which chromosome the mutation is located on and what the mutation is.

Moreover, common, known and synonymous variants were not included in their final analysis. In our study we will investigate all variant types because our aim is to determine what pathways variants occupy and their interactions with other variants. Eliminating variants may well result in lose of

In cross B, a red-eyed female fly was placed into a vial with a white-eyed male fly and a red- eyed male fly for a breeding period of two weeks. At least eight red-eyed females were produced from this cross. These eight females were used to conduct a polymerase chain reaction. Comparing to the control groups, the results show that seven out of eight flies has the Xw+ Xw genotype because all of them had both bands appear on the gel when both alleles were present. This indicates that all of them are heterozygous. They are all red-eye females. Fly 7, however either of the band appear. This means that an error occurred, and one possible error could be not enough DNA were extracted therefore the gel could

Drosophila Melanogaster is a fruit fly that is commonly used for genetic studies (reference 2). It is an excellent organism for genetic studies because it is small, inexpensive and easy to culture. It occupies little space, and requires simple food (reference 3). Also, it completes its life cycle in about 10-14 days at 25ºC and It produces large numbers of offspring (reference 3).Moreover, it has abundance of heredity variations, and it has a small number of chromosomes which are easily located in the large salivary gland cells (reference 3).There are four important stages in a Drosophila's life cycle consist of the egg, larva, pupa, and adult. Both Drosophila male and female have noticeable features that distinguish them apart.

For each pair of traits crossed, one alternative was not expressed in the F1 hybrids, although it reappeared in some F2 individuals