DNA "Fingerprinting" Worksheet
In this hypothetical paternity case, four autoradiographs show DNA "fingerprints" taken from three individuals: a mother, her child, and the child's alleged father. Each autoradiograph compares equivalent DNA segments from the three individuals. The two dark bands in each column represent one individual's DNA segments -- one inherited from that individual's biological mother and the other from the biological father. These segments differ in length from person to person; for this reason they are used as genetic markers. Here, each length is designated by a letter, A through O. The two letters associated with each segment indicate the individual's genotype.
- Under each column in the autoradiograph, write the letters associated with each individual's genotype. For example, the genotype of the mother in the first column is A/D. Then, circle the letter in the child's genotype that represents the gene inherited from the mother.
- Which "letters" must the child have inherited from its father?
- Based on this information, what evidence suggests that the alleged father could be biologically related to the child?
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Earth and Life Sciences Program Contents
The Long View
Seeing and Believing
In-Depth Investigation: The Dating Game
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