1. Formulate a hypothesis about whether a population of friends, family, and/or acquaintances is similar or different to you in appearance. Obviously, the population that is queried may guide this hypothesis.
2. Choose at least 14 people, including yourself, as subjects. Using the following Trait Description checklist, gather data about each individual, and mark the results on Data Table 1. Note that the first person's data has been added as an example of how to record the data.
3. After you have queried 14 people, transfer the table results to the genetic traits chart, Figure 1. Begin in the center and work from the center outward. Mark the outer circle at the point that the last allele is found. Note that the first entry is completed for you. In the chart, capital letters equate to a dominant and hybrid gene pair (FF and Ff). The lower case letters equate to a totally recessive gene pair (ff).
Human Genetics
Data Table 1: Single-Gene Traits of a Selected Population
Subject # > 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Total
XX Female xx
XY Male
FF, Ff = unattached
ff= attached ff
RR, Rr = roller R
Rr = can't roll
SS, Ss = straight thumb
ss = best thumb ss
MM, Mm= hair
mm= no hair
TT, Tt= left on top T
tt = right on top
LL, Ll = two tendons
L
ll = three tendons
Exercise 1: Patterns in Human Inheritance Traits
Questions
A. What observations can be made about the collection and charted data?
B. Are any two people exactly the same? If so, how closely are they related?
C. Is your hypothesis supported by the findings? What statistical tool might help you to make this decision?
D. In the totals that you recorded in Table 1, did you find that the number of dominant phenotypes were greater than, equal to, or less than the recessive phenotypes?
E. Can you explain what possible genotypes are suggested by this pattern? Does this vary by trait?
F. Would you expect this outcome? Why or why not?
G. How would changing the level of the mapped traits affect the chart? For instance, if the alleles for male or females were on the outer rim of the chart, rather than in the middle, how would the pattern observed differ from Figure 10-1?
H. List several other traits that humans have that are governed by genetics.
I. Would your data vary if you went to another part of the world, for instance, China?
J. Why might collected data show different patterns for different cultural population?
K. Would you expect that the pattern would be different if collected 100 years ago instead of today? Why or why not?
L. If you had percentages of dominant and recessive genes present for the total number of alleles of a trait for the entire world would you expect that percentage to change over 100 years?
Exercise 2: Human Chromosomes and the Human Genome Project
Results
Report on your findings. Your report should be limited to a page in length and may incorporate the outline of research points above.
Questions
A. What is the purpose of this exercise?
B. What is the prognosis on genetic diseases in the future? Do you believe that microsurgery to "fix" chromosomal aberrations will some day prevent the diseases that are listed in the List of Genetically Mediated Diseases in Humans?
Laboratory Summary
What have you learned from doing this laboratory?
References