In a control experiment, a plasmid containing a HindIII recognition sequence within a kanamycin resistance gene is cut with HindIII, re-ligated, and used to transform E. coli K12 cells. Kanamycin-resistant colonies are selected, and plasmid DNA from these colonies is subjected to electrophoresis. Most of the colonies contain plasmids that produce single bands that migrate at the same rate as the original intact plasmid. A few colonies, however, produce two bands, one of original size and one that migrates much less far down the gel. Diagram the origin of this slow band as a product of ligation.

Three independently assorting STR markers (A, B, and C) are used to assess the paternity of a colt recently born to a quarter horse mare. Blood samples are drawn from the mare, her colt, and three possible male sires (S₁, S₂, and S₃). DNA at each marker locus is amplified by PCR, and a DNA electrophoresis gel is run for each marker. Amplified DNA bands are visualized in each gel by ethidium bromide staining. Gel results are shown below for each marker. Calculate the PI and CPI based on these STR markers, using the following population frequencies: A₁₂ = 0.12, A₁₀ = 0.18; B₁₈ = 0.08, B₁₂ = 0.17; C₁₆ = 0.11, C₁₄ = 0.20.

Three independently assorting STR markers (A, B, and C) are used to assess the paternity of a colt recently born to a quarter horse mare. Blood samples are drawn from the mare, her colt, and three possible male sires (S₁, S₂, and S₃). DNA at each marker locus is amplified by PCR, and a DNA electrophoresis gel is run for each marker. Amplified DNA bands are visualized in each gel by ethidium bromide staining. Gel results are shown below for each marker. Evaluate the data and determine if any of the potential sires can be excluded. Explain the basis of exclusion, if any, in each case.

What is the main purpose of genome-wide association studies (GWAS)? How can information from GWAS be used to inform scientists and physicians about genetic diseases?

Describe how the team from the J. Craig Venter Institute created a synthetic genome. How did the team demonstrate that the genome converted the recipient strain of bacteria into a different strain?

What advantages do cDNA libraries provide over genomic DNA libraries? Describe cloning applications where the use of a genomic library is necessary to provide information that a cDNA library cannot.

The bacteriophage lambda genome can exist in either a linear form or a circular form.

Diagram the resulting fragments as they would appear on an agarose gel after electrophoresis.

To create a cDNA library, cDNA can be inserted into vectors and cloned. In the analysis of cDNA clones, it is often difficult to find clones that are full length—that is, many clones are shorter than the mature mRNA molecules from which they are derived. Why is this so?

A hereditary disease is inherited as an autosomal recessive trait1. The wild-type allele of the disease gene produces a mature mRNA that is 1250 nucleotides (nt) long. Molecular analysis shows that the mature mRNA consists of four exons that measure 400 nt (exon 1), 320 nt (exon 2), 230 nt (exon 3), and 300 nt (exon 4). A mother and father with two healthy children and two children with the disease have northern blot analysis performed in a medical genetics laboratory. The results of the northern blot for each family member are shown here. Based on your analysis, what is the most likely molecular abnormality causing the disease allele?