The human genome reviewed

This exercise is a part of Educator Guide: An Open Book / View Guide

1. Find an article about the completion of the Human Genome Project. When was the first human genome, or entire set of genetic instructions, sequenced? How much did it cost and how long did it take? How does that effort compare with current human genome sequencing?

Directions: After reading the article An open book,” log in to your Science News in High Schools account and use the Search page to answer these questions. Make sure you adjust the filters to include articles written before 1999, if the question requires you to do so.

Possible student response: The Science News article “Moving On: Now the human genome is really done,” published 4/19/2003, reports that the first human genome was mostly finished by 2000 and finalized in 2003. The effort cost several billion dollars and took more than a decade. By contrast, now most of a person’s genome can be sequenced for thousands of dollars in less than one day. The cost and time required will likely continue to decrease in the future.

2. Find an article about genome sequencing with a graph that shows the historical changes in duration and cost. Summarize the overall trend and support your statement with appropriate data.

Possible student response: The Science News article “The gene sequencing future is here,” published 2/6/2014, includes a graph that shows improvements in genome sequencing cost and time between 1996 and 2014. The sequencing speed in kilobases per day (1 kilobase = 1,000 DNA bases, or nucleotides) went from around 10 kilobases/day in 1996 to around 300 million/day in 2014. For reference, the complete human genome is approximately 6 gigabases, or 6 million kilobases. The sequencing cost fell from around $1,000 per kilobase (or $1/base) in 1996 to around $0.002 per kilobase (or $0.000002/base) in 2012.

3. Find and summarize an article about sequencing a virus’s genome. Just as human genome sequencing has many applications, what are some potential applications of viral genome sequencing?

Possible student response: The Science News article “Sequencing virus genome to cure the common cold,” published 2/12/2009, describes how the genomes of all 99 known strains of human rhinovirus — a virus that can cause the common cold — were sequenced. When researchers sequenced the genomes of 10 virus strains obtained from patients with colds, the scientists found that those 10 strains had accumulated mutations that existing reference strains did not have. This suggests that rhinoviruses are continuing to evolve. Some potential applications of such viral sequencing might include developing vaccines to protect against the common cold and predicting how virulent a particular rhinovirus strain will be.