Sample Exam IV

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=90 BGCOLOR="#006699" TEXT="#080000" bgproperties="fixed" background="109285a1erlcgo.gif"> <div> <FONT SIZE="5" COLOR="#FFCC66" FACE="Arial" ><B>Human Genetics</B></FONT><B>     |     </B><A HREF="index.htm" TARGET="_top" TITLE="Human Genetics"><U><B>home</B></U></A></div> <div> <A HREF="id36.htm" TARGET="_top" TITLE="Syllabus"><U>Syllabus</U></A>   |   <A HREF="id82.htm" TARGET="_top" TITLE="Journal Club Days"><U>Journal Club Days</U></A>   |   <A HREF="id27.htm" TARGET="_top" TITLE="Journal Guidelines"><U>Journal Guidelines</U></A>   |   <A HREF="id38.htm" TARGET="_top" TITLE="Journal Club Guidelines"><U>Journal Club Guidelines</U></A>   |   <A HREF="id90.htm" TARGET="_top" TITLE="Genetics Education Model Project"><U>Genetics Education Model Project</U></A>   |   <A HREF="id53.htm" TARGET="_top" TITLE="Recessive Inheritance Model"><U>Recessive Inheritance Model</U></A>   |   <A HREF="id98.htm" TARGET="_top" TITLE="figures"><U>figures</U></A>   |   <A HREF="id52.htm" TARGET="_top" TITLE="Sample Exam I"><U>Sample Exam I</U></A>   |   <A HREF="id62.htm" TARGET="_top" TITLE="Sample Exam II"><U>Sample Exam II</U></A>   |   <A HREF="id63.htm" TARGET="_top" TITLE="Sample Exam III"><U>Sample Exam III</U></A>   |   <B>Sample Exam IV</B></div> <div> </div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#FFCC66" TEXT="#080000" background="108d2c00dkelyh.gif"> <bR> </td> <td valign="top" height=390 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <I>Sample Exam IV</I></div> <bR> <div> 1.  Describe a situation, hypothetical if you wish, in which a maternal genetic mutation is harmful to an embryo that has wildtype genes.</div> <bR> <div> 2. What is heterozygote advantage?  How does this idea help explain the prevalence of a particular mutation in a population?</div> <bR> <div> 3. If a male lacks the ability to produce testosterone, would you expect to find testes or ovaries and male or female external genitalia in this XY child?  <I>Briefly</I> explain.</div> <bR> <div> 4. Below you will find a scaled-down version a pedigree given to me by a previous human genetics student.  This student is not contained within this small version, but she had some questions about what degree of relatedness her cousins had.  So, let's help her out.</div> <bR> <div> <IMG SRC="0dfd00a0.gif" border=0 width="208" height="266" ALT="Adobe PhotoDeluxe Business Edition Image" ALIGN="LEFT" HSPACE="0" VSPACE="0"></div> <div> a. What is the probability of a lethal phenotype for any child of Debbie and Melvin's if William and Claudia carry eight lethal alleles each?</div> <bR> <div> b.  Is a first cousin mating (not shown here) or an uncle-niece mating (Debbie-Melvin) more likely to produce a lethal phenotype?  Briefly explain.</div> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <bR> <div> 5. You are studying vocal cord development in humans.  You perform analyses of the tissue and identify four genes that are expressed in this tissue and name them <I>soprano</I>, <I>alto</I>, <I>tenor</I>, and <I>bass</I>.  Now you begin to study how the gene expression pattern is regulated by making mutant human clones in each gene and observing whether the other genes are transcribed.  Your results are shown in the table below.  RNA present is noted by +; RNA absent is noted by -.  (<B>HINT</B>:  It may be easier to start with two genes and figure out their relationships and then add the other genes one at a time.) </div> <bR> <div> <TABLE BORDER="2" CELLPADDING="1" CELLSPACING="1" WIDTH="365" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 39 WIDTH="75"><div> <B>embryo</B></div> <div> <B>type</B></div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <I><B>soprano</B></I><B> RNA</B></div> </tD> <tD VALIGN=TOP><NOBR><div> <I><B>alto</B></I><B> RNA</B></div> </NOBR></tD> <tD VALIGN=TOP WIDTH="63"><div> <I><B>tenor </B></I><B>RNA</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <I><B>bass </B></I><B>RNA</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="75"><div> wildtype</div> <div> embryo</div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="68"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="75"><div> <I>soprano</I> mutant</div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="68"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>-</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="75"><div> <I>alto</I></div> <div> mutant</div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="68"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="75"><div> <I>tenor </I>mutant</div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="68"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 38 WIDTH="75"><div> <I>bass</I></div> <div> mutant</div> </tD> <tD VALIGN=TOP WIDTH="66"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="68"><div> <B>-</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>+</B></div> </tD> <tD VALIGN=TOP WIDTH="63"><div> <B>-</B></div> </tD> </tR> </TABLE></div> <bR> <div> Diagram the regulatory pattern using gene names and arrows.  Briefly explain your reasoning.</div> <bR> <div> 6. Two years from now you are a special agent forensic scientist and are working a crime scene in which the rapist was scratched by the victim.  You collect the rapist's skin from the victim's fingernails to run DNA fingerprinting tests in comparison to two suspects.  You find a match for each of the five loci you tested.  In the following table you will find the real-life alleles and their real-life frequencies courtesy of Cellmark Diagnostics. Please show your work</div> <bR> <bR> <DIV ALIGN="LEFT"></DIV> <div> <TABLE BORDER="2" CELLPADDING="1" CELLSPACING="1" WIDTH="678" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP COLSPAN=5 HEIGHT= 20 WIDTH="660"><div> <B>DNA profile</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 58 WIDTH="131"><div> <B>Locus</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> <B>Allele</B></div> </tD> <tD VALIGN=TOP WIDTH="135"><div> <B>allele</B></div> <div> <B>frequency</B></div> </tD> <tD VALIGN=TOP WIDTH="123"><div> <B>equation used to calculate probability</B></div> </tD> <tD VALIGN=CENTER WIDTH="129"><div> <B>genotype frequency</B></div> </tD> </tR> <tR> <tD VALIGN=TOP ROWSPAN=2 HEIGHT= 19 WIDTH="131"><div> <B>DQAI</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> 2</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.087</div> </tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="123"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="123" HSPACE="0" VSPACE="0"></tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="129"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="129" HSPACE="0" VSPACE="0"></tD> </tR> <tR> <tD VALIGN=TOP WIDTH="130"><div> 4.2</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.563</div> </tD> </tR> <tR> <tD VALIGN=TOP ROWSPAN=2 HEIGHT= 19 WIDTH="131"><div> <B>D7S8</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> A</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.544</div> </tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="123"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="123" HSPACE="0" VSPACE="0"></tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="129"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="129" HSPACE="0" VSPACE="0"></tD> </tR> <tR> <tD VALIGN=TOP WIDTH="130"><div> B</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.456</div> </tD> </tR> <tR> <tD VALIGN=TOP ROWSPAN=2 HEIGHT= 19 WIDTH="131"><div> <B>HBGG</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> A</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.558</div> </tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="123"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="123" HSPACE="0" VSPACE="0"></tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="129"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="129" HSPACE="0" VSPACE="0"></tD> </tR> <tR> <tD VALIGN=TOP WIDTH="130"><div> C</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.005</div> </tD> </tR> <tR> <tD VALIGN=CENTER ROWSPAN=2 HEIGHT= 19 WIDTH="131"><div> <B>TPO</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> 10</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.053</div> </tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="123"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="123" HSPACE="0" VSPACE="0"></tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="129"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="129" HSPACE="0" VSPACE="0"></tD> </tR> <tR> <tD VALIGN=TOP WIDTH="130"><div> 10</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.053</div> </tD> </tR> <tR> <tD VALIGN=CENTER ROWSPAN=2 HEIGHT= 19 WIDTH="131"><div> <B>LDLR</B></div> </tD> <tD VALIGN=TOP WIDTH="130"><div> A</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.437</div> </tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="123"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="123" HSPACE="0" VSPACE="0"></tD> <tD VALIGN=TOP ROWSPAN=2 WIDTH="129"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="129" HSPACE="0" VSPACE="0"></tD> </tR> <tR> <tD VALIGN=TOP WIDTH="130"><div> B</div> </tD> <tD VALIGN=TOP WIDTH="135"><div> 0.437</div> </tD> </tR> </TABLE></div> <bR> <div> a.  What is the probability that another person has the same genotype for all loci noted above?</div> <bR> <div> b.  How many people in the Nashville area (1.3 million total) would also have this genotype?</div> <bR> <div> 7. A colleague of yours is studying candidate tumor suppressor genes.  This colleague performed two experiments with two different potential tumor suppressor genes.  Your colleague transfected cancer cells with vector alone, vector + the candidate tumor suppressor gene, or vector + a known tumor suppressor gene.  The results are shown below.</div> <bR> <div> </div> <bR> <div> a. Your colleague mistakenly interprets his results as showing that both candidate genes show tumor suppressor activity.  However, you know that only one gene shows clear evidence of being a tumor suppressor gene.  Which one?  Briefly explain.</div> <bR> <div> b.  Your analysis of the data reveals that the other experiment is not conclusive.  What is the problem with the “other” experiment?</div> <bR> <div> 8. Briefly describe the three classes of human dysmorphology and the differences between each.  Be sure to give an example of each or note whether each is symmetrical or asymetrical.</div> </td> </tr></table></body>