PS 4 answers - LS4 Problem Set 4, 2010 Transgenics and...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
LS4 Problem Set 4, 2010 Transgenics and homologous recombination Corresponding Lectures: November 17, 19 (maybe the beginning of Nov 22) Corresponding Reading: Hartwell et al., 744-745, 851-852, 858-859 Corresponding Quiz: November 29-December 3 Problem 1 . There is only one region of homology in this transgene. Another region of homology is needed on the other side of the neoR gene. Problem 2 a) If no transgene integrates into the genome neomycin will kill the cell, since cells are naturally vulnerable to neomycin. b ) In all three cases, if the transgenes integrate randomly into the genome, cells will be killed by gancyclovir, since all of the transgenes include the TK gene which turns gancyclovir into a toxin. c) If homologous recombination occurs at the sites of homology, transgenes 1 and 3 will be killed by gancyclovir, since TK will be integrated into the genome and turn it into a toxin. Transgenes 2 and 3 will be killed by neomycin, since cells will lack the neomycin resistance gene. Problem 3. G can simply outcross her one heterozygous mutant female to a wild-type mouse. Half of the progeny will be heterozygous for the HFG gene. She can then cross two of these sibling mice with each other and ¼ of their progeny will be homozygous for the HFG mutation. Problem 4. To determine what will happen in the progeny, only the germline matters. The chimeric cells in the germline will be heterozygous for the knockout, so after meiosis, the percent of sperm and eggs that carry the knockout will be half as many (e.g. if 50% of germline precursors are heterozygous, 25% of the sperm will carry the knockout allele) A) When the chimeric male is crossed to a wild-type female, 75% of the progeny will be
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

PS 4 answers - LS4 Problem Set 4, 2010 Transgenics and...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online