Humans, Chimps, and a Missing Chromosome

Date: 6/3/2020
Time: 2:00 PM
Duration: 30 minutes
Presenter(s): Uwe Hilgert, BIO5 Institute, University of Arizona
Audience: Grades 9-12, Undergraduates
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Activity description:

DNA and RNA encode information in the sequences of their nucleotide building blocks just as languages encode information in sequences of letters, words, and sentences. The advent of DNA sequencing technology in 1970 enabled us to decipher the sequence of nucleotides in DNA. Today, DNA sequences can be obtained from scientific journals, databases, and web sites—frequently free of charge.

Bioinformatics uses information technology, such as computers and computer programs, to study the information in DNA and proteins. In this activity, you will use bioinformatics tools to understand how DNA sequence similarities reveal relationships between species. You will start with a puzzling question: why do humans have fewer chromosomes than chimpanzees? You will use DNA sequences to answer this question and uncover relationships between humans and other primates, as well as discern differences between us and them.

In this in silico (on the computer) laboratory you will:
• Use tools at the National Center for Biotechnology information to discover a major difference between the genomes of humans and chimpanzees
• Use BLAST sequence searches to determine the fate of a chromosome missing in humans
• Use phylogenetic bioinformatics tools to time the rise of a major genomic difference in primates
• Use chromosome alignments to determine the fate of a surplus centromere