CHARLOTTE — Twelve students in Charlotte Catholic High School’s Advanced Placement Biology class recently spent a day at Clemson University to study the genetics of bitter taste.
The students and their teacher, Gwenn Freeman, were quite excited to conduct an experiment of this magnitude, using laboratory equipment not available to most high school students.
The students were asked to study the PTC gene, an inherited trait which determines whether people taste phenylthiocarbamide, or PTC, as extremely bitter, slightly bitter or not bitter at all. During the 1930s, geneticists determined that there is an inherited component that influences how a person tastes PTC. In 2003 geneticists discovered that the ability to taste PTC is conveyed by a single gene that codes for a taste receptor on the tongue.
PTC is not found in nature, but the ability to taste it is strongly related to the ability to taste other bitter substances in nature – many of which are poisonous. The ability to taste bitter substances evolved as a way to prevent early humans from eating toxic plants.
Students began their study with a simple test in which they tasted paper containing PTC. Most of the students tasted the PTC as slightly bitter, while a few did not taste it at all, and one tasted it as extremely bitter.
Next, the students took samples of their own DNA, amplified a small segment of each sample approximately 500 billion times using a Polymerase Chain Reaction, and prepared it with the addition of primers and a hot/cold protocol. Last, students used DNA gel electrophoresis to see whether they inherited a dominant gene, a recessive gene or a combination of the two genes from their parents.
“It was a terrific learning experience,” Freeman said. “We enjoyed fantastic instruction from the lab instructor at Clemson, and even had time to enjoy lunch at a new cafeteria and take a brief stroll across campus.”
— Carolyn Kramer Tillman, Special to the Catholic News Herald
CHARLOTTE — Four Charlotte Catholic High School choral students were selected to participate in the 69th annual Mars Hill University Choral Festival Feb. 3-4.
Jonathan Huth, Chelsea Smith, Emma Story and Maura Streppa were selected through auditions held last October. More than 800 students across the state auditioned, and from those auditions, 280 were chosen for the festival choir. Dr. Craig Jessop, the former conductor of the Mormon Tabernacle Choir, served as the guest conductor and clinician for the two-day festival, which culminated in a concert held Feb. 4.
The Mars Hill University Choral Festival was established in 1949 as an effort to improve choral music in the high schools of western North Carolina. In its early years, the festival was comprised of about 15 schools in the area surrounding Mars Hill University. It has grown to become one of the premiere choral festivals in North Carolina, and is thought to be the longest continuously-running festival of its type in the southeast.
Dottie Tippett, choral director and fine arts chair at the high school, noted that Jessop commented at a choral directors’ luncheon that he doesn’t know of another state that offers such a prestigious festival for high school students. “It’s such an honor for Jonathan, Chelsea, Emma and Maura to be selected,” she said. “We are all very proud of them.”
— Carolyn Kramer Tillman