SHARE
Senior Randi Block col­lected, mea­sured, and ana­lyzed approx­i­mately 250 ticks for her research project. Randi Block | Courtesy

Ticks stopped both­ering senior biology major Randi Block after she had to collect and crack them open for a year’s worth of research.

Block studied the American dog tick as a carrier of rick­ettsia, a path­o­genic bac­teria that causes Rocky Mountain Spotted Fever.

Even though she said ticks dis­gusted her at the beginning of the project, she still decided to follow Asso­ciate Pro­fessor of Biology Jeffrey VanZant’s sug­gestion to research them.

“My original question was looking at the pop­u­lation of deer ticks which carry Lyme disease and they were unknown whether they were present in Hillsdale County,” Block said. “I had all the primers to run stuff for Lyme disease detection, but we never actually found any deer ticks.”

But after months of hard work, Block did dis­cover that there are ticks car­rying rick­ettsia in Hillsdale County and in Northern Michigan, where Hillsdale’s G.H. Gordon Biology Station is located.

Although a majority of ticks carry a non­in­fec­tious form of rick­ettsia, Block looked for the presence of a surface protein that is com­monly found in ticks car­rying an infec­tious form of rick­ettsia.

“We found that in Hillsdale County, about 10.8 percent of ticks carry rick­ettsia, which means they can cause disease. I also did the same study up in Lake County, which is where we have our bio­station, and up there it was about 7.2 percent,” Block said.

In order to begin her search for rick­ettsia, she first had to collect hun­dreds of ticks. She began col­lecting them at the bio­station and in Hillsdale County last summer.

Block col­lected about 250 dog ticks by dragging a piece of canvas through brush and grass for the ticks to grab on to.

“Then you check your legs, because they are also all over you,” Block said. “So you get about half on the canvas, half on yourself, pluck them off, and stick them in ethanol.”

During col­lection, Block had the help of sophomore Luke Woltanski in gath­ering the ticks, even though he said he was orig­i­nally ter­rified of the critters.

“I got to draw this big cor­duroy cloth all over these areas at the bio­station,” Woltanski said. “We put our bodies on the line for it. There was one that Dr. Houghton had to pull out of the back of my head. He really got in there and in his effort to dig in under the tick’s mouth­piece, he rammed my head into the table. It was hilarious.”

Block said she also quickly got over her aversion to ticks.

“You get past a certain point where you are just covered with like 20 of them, and you don’t even care anymore, you just get them off,” Block said.

After Woltanski helped Block collect all her ticks, sophomore Andrew Rademacher helped her with DNA sequencing in the lab. While working in the con­ser­vation genetics lab, Rademacher ended up playing a sig­nif­icant role in the ticks’ genetic analysis.

Rademacher had to replicate and extract the DNA from the ticks so that Block could determine whether or not that par­ticular tick carried the bac­teria.

“I would homog­enize the ticks, so basi­cally destroy it, and pull all the DNA out. Then from that DNA, I would take it and I would optimize for a system called PCR, which then repli­cates a single strand to an obscene amount,” Rademacher said.

Based on the analysis, Block deter­mined that some of the ticks con­taining the surface protein only con­tained an older form of rick­ettsia — not the rick­ettsia that causes spotted fever. It is unclear whether that older form of rick­ettsia can cause disease, Block said.

Opti­mization usually takes several months, but Rademacher was lucky and found effective PCR con­di­tions in only two weeks. But even with this good luck, there was a lot of hard work he had to put in.

“It smelled bad,” Rademacher said. “Ticks have a really weird smell, and they look alive no matter what you do. You poke them and even when they’re dead, they move. But it was fun.”

Luckily neither Block, Woltanski, or Rademacher con­tracted any dis­eases after dealing with ticks for months.

“I only got bit once,” Block said. “And the tick that bit me didn’t have rick­ettsia — I checked.”