Give a brief definition of a homeobox.
Two forms of hemophilia are determined by genes on the X chromosome in humans.
Assume that a phenotypically normal woman whose father had hemophilia is married to
a normal man. What is the probability that their first son will have hemophilia?
Describe, in general terms, the aims of gene therapy.
In Drosophila, what is the order of function of the segmentation genes?
What distinguishes sex-limited from sex-influenced inheritance?
Assume that in a Hardy-Weinberg population, 9% of the individuals are of the
homozygous recessive phenotype. What percentage are homozygous dominant?
Sister chromatid exchanges increase in frequency in the presence of X-rays, certain
viruses, ultraviolet light, and certain chemical mutagens. In what autosomal recessive
disorder is there known to be an increase in sister chromatid exchanges?
Briefly describe what is meant by gene therapy.
What is meant by the designation EcoRI?
Studies of Neurospora led to the ________ statement, whereas studies of human
hemoglobin led to the ________ statement.
Provide a formal equation for h2 (narrow-sense heritability).
Bacteriophages that cannot undergo lysogeny but can infect bacteria are called
________.
Alternative forms of a gene are called ________.
For the purposes of this question, assume that being Rh+ is a consequence of D and that
Rh– individuals are dd. The ability to taste phenylthiocarbamide (PTC) is determined by
the gene symbolized T (tt are nontasters). A female whose mother was Rh– has the MN
blood group, is Rh+ and a nontaster of PTC, and is married to a man who is MM, Rh–,
and a nontaster. List the possible genotypes of the children. Assume that all the loci
discussed in this problem are autosomal and independently assorting.
Assume that the genes for tan body and bare wings are 15 map units apart on
chromosome II in Drosophila. Assume also that a tan-bodied, bare-winged female was
mated to a wild-type male and that the resulting F1 phenotypically wild-type females
were mated to tan-bodied, bare-winged males. Of 1000 offspring, what would be the
expected phenotypes, and in what numbers would they be expected?
In a mating between individuals with the genotypes IAIB x ii, what percentage of the
offspring are expected to have the O blood type?
What are two commonly used DNA landmarks for mapping human genes?
Describe Bar mutations in Drosophila melanogaster.
Assume that a base addition occurs early in the coding region of a gene. Is the protein
product of this gene expected to have more or fewer altered amino acids compared with
the original gene with a base deletion late in the coding region?
Describe a somewhat extraordinary finding related to the Tetrahymena telomerase
enzyme.