Newly discovered leprosy genomes help fill historic gaps

October 12, 2020

History books often link disease and colonization, in which explorers unknowingly bring with them illnesses that spread to native people. New findings on the origin of leprosy in the Pacific Islands, however, contradict this suggestion. 

Arizona State University graduate students Kelly Blevins and Adele Crane are the primary co-authors of a study identifying nine new genomes of Mycobacterium leprae, one of the two pathogens that cause leprosy. Previously, only two other genomes of M. leprae had been recovered in the Pacific Islands.  Map of the Pacific Islands M. Leprae Genomes Figure 1. “Map of the Pacific showing source locations of novel and previously sequenced M. leprae strains from branch 0 and branch 5. Novel strains from this study all fall within these branches and are shown as diamonds,” the researchers wrote. “Comparative data are shown as circles.” Strains of M. leprae have geographical associations. The newly discovered genomes belonged to strain 0, which is predominantly found in East Asia, and branch 5, which is largely the Pacific Islands. Reprinted with permission from the Philosophical Transactions B journal. Download Full Image

These nine novel strains fall into the most ancient lineages in the family tree of M. leprae, branches 5 and 0. The last time that these branches shared a common ancestor was almost 4,000 years ago.

These findings suggest that leprosy was not introduced to the Pacific Islands during colonialism in the 1800s, as previously thought. Colonialism may have brought subsequent strains of leprosy to the Pacific Islands, but those strains would belong to different branches of the evolutionary tree. 

“Specifically, our results suggest that leprosy was probably present in the Pacific prior to European contact and likely spread via trade/voyaging networks,” said Anne Stone, ASU Regents Professor and senior co-author of the research. 

Leprosy is a chronic infectious disease that can be fatal. While it is still around today, it can be treated with antibiotics.

The tissue samples for this study came from the Hawaiian Pathologists’ Laboratory. Blevins and Crane received the samples at ASU’s Lab of Molecular Anthropology, selected and adapted a method for extracting DNA, analyzed data and wrote the manuscript.  

The research team also conducted bioinformatics work, comparing their data with publicly available M. leprae genomic data records. (See Figure 1 from the research paper.) 

This additional data also helped Blevins and Crane analyze relationships between strains and create phylogenetic trees. Crane called them the “family trees” of the pathogen, showing the evolutionary history of the various strains.

ASU graduate students lead the study

Blevins and Crane are both doctoral students at ASU — Blevins in anthropology at the School of Human Evolution and Social Change, and Crane in evolutionary biology at the School of Life Sciences. They designed the study and executed the laboratory work and data analysis. 

Blevins and Crane come from different areas of primary research and past academic work, but now they both want to know where diseases come from.

Blevins’ work and research during her undergraduate and graduate studies focused on osteology (studying bones) and paleopathology (studying ancient disease). This background provided a good foundation for a transition into genomics research.

“You can only tell so much from bones,” Blevins said. “They’re like a signpost saying ‘something was causing disease here,’ so getting into genomics helps better piece together what was going on.”

Crane comes from a background in molecular biology. She originally wanted to become a veterinarian and study wildlife diseases, but her research journey has led her to study how new interactions with the environment are affecting humans. She hopes to work in government research or surveillance of modern diseases. 

Original concept and implications for future research

This research concept came from Keolu Fox, a native Hawaiian and University of California, San Diego assistant professor. He is working to expand the genome database to include more underrepresented populations.

Crane said future research will include more data, including more samples and different types of samples.

“These nine genomes have formed our understanding of leprosy in the Pacific right now,” Crane said. “We have a much better picture of where it is and what’s going on.” 

But, she is interested in gathering data from a wider geographic area. Crane is continuing to research leprosy with the Hawaiian Pathologists’ Laboratory as part of her dissertation, for which she is researching bacterial populations within a host. 

The paper “Evolutionary history of Mycobacterium leprae in the Pacific Islands” was published in a special themed issue of the Philosophical Transactions B journal, “Insights into health and disease from ancient biomolecules.”

Taylor Woods

Communications program coordinator, School of Human Evolution and Social Change


Donations to ASU fund COVID-19 assistance, many other causes

October 12, 2020

The COVID-19 pandemic upended students’ academic and personal lives during the spring, leaving several students in need of swift assistance.

Yaritza Hernandez Gil, a first-generation student who is double majoring at Arizona State University, was working two jobs to pay for college and living expenses when her work hours were cut because of the pandemic. Students wearing masks and social distancing Download Full Image

Around the same time, an ASU Law student was in the United Kingdom for an externship when the pandemic started shutting down countries, and she needed to quickly return to the United States. She was unprepared to incur the last minute travel expense.

Sun Devil supporters stepped up to aid both of these students and many more who found themselves in crisis from the pandemic. Donors provided more than 4,260 gifts earmarked for COVID-19-related student support, research and community resources between March and June, when the ASU Foundation’s fiscal year ended. Overall, the ASU Foundation raised $290 million during the year for ASU students, faculty, research and community programs.

“The engagement and generosity of ASU donors reflects their amazing commitment to student success and the advancement of new knowledge,” ASU President Michael Crow said. “In a year of unprecedented challenges and opportunities, support for our mission by those who share our vision has remained constant and we are deeply appreciative of that dedication to ASU and our learners.”

Hernandez Gil received emergency crisis funding in the form of grocery store gift cards from the Bridging Success program, which assisted her and other former foster youth who needed financial help.

“It’s tough to not get a paycheck,” Hernandez Gil said. “But this allows me to have meals for myself.”

Rick Barry, Sandra Day O’Connor College of Law alumnus (’73), already had a scholarship established in the college, but wanted to do more for ASU when the pandemic hit. That’s when he learned about the Law Annual Fund, which supports urgent needs of the college at the discretion of the dean, and he was sold on the notion of helping as many student as possible.

“For those families that don’t have traditional support that I’ve always enjoyed, it’s really tough,” Berry said. “I’m fortunate enough to be in a position to help.”

Berry’s gift helped several ASU Law students including the one stranded in the United Kingdom. The student’s airfare was covered by the law fund, along with an Airbnb rental in which to complete the mandatory 14-day quarantine period when she returned. Since Berry’s gift, more than 40 other supporters donated to the fund.

When many community resources were forced to close or move to virtual offerings, donors stepped in to ensure their services could continue. Donations to the ASU Speech and Hearing Clinic enabled many of the clinic’s telehealth services to be free during the summer.

Additional private support aided the Biodesign Institute’s COVID-19 research and testing kits and provided personal protective equipment to medical professionals.

“We are very grateful for the generosity we received, both for COVID-19-related resources and for donations to support ASU’s vision to solve grand problems that will improve lives and enhance our communities,” ASU Foundation CEO Gretchen Buhlig said. “Donors have the ability to support causes they are passionate about and every donation – large or small – makes an impact on students, faculty and the community.”

Donors enabled more than 7,900 unique undergraduate and graduate students to receive $29.2 million in scholarships last school year, according to preliminary data counts. That is a nearly 6% increase in students who received a scholarship compared with the preceding year.

Scholarship recipient Amalie Strange is a first-generation student who graduated in May with bachelor’s degrees in biological sciences and Spanish from The College of Liberal Arts and Sciences, and she returned this fall in pursuit of her PhD in animal behavior.

“I don't think I would have been able to make it to this point if I didn't have those scholarships,” Strange said.

Four siblings – Brett, Chase, Scott and Jenna Fitzgerald – who graduated from ASU with distinction from Barrett, The Honors College established a $25,000 endowed scholarship to give back to the community that gave them so much.

“Barrett has enabled my entire family to find fast and frequent success in our careers and we thought it fitting to, in turn, start paying back early and often” Chase said.

Support for faculty remained strong with 39 gifts totaling $4.8 million for faculty chairs and professorships. Rhett Larson, a professor in the Sandra Day O’Connor College of Law was recently named the first Richard Morrison Professorship in Water Law.

“Richard Morrison has been my friend and mentor since I was a young water lawyer,” Larson said. “He’s also been a leader in Arizona water policy. It’s an honor to hold a position that bears his name.”

Faculty not only benefitted from private support, but also donated to causes they were passionate about. Nearly 1,600 faculty and staff donated to ASU during the fiscal year.

Returning faculty member Alexandra Navrotsky donated money to establish the Navrotsky Eyring Center for Materials of the Universe to bring science and engineering together for materials and space exploration.

Private support also funded a variety of programs and initiatives during the year.

One of those gifts came from State Farm to establish the Pathways for the Future initiative. The $30 million gift will provide education and career development opportunities for high school and community college students, as well as adults in the workforce who need to update their skills.

Campaign ASU 2020 publicly launched in January 2017 to raise the long-term fundraising capacity of the university and focuses on six priorities including student access and excellence; student success; the academic enterprise; discovery, creativity and innovation; enriching our communities; and Sun Devil competitiveness. The fundraising campaign ends on Dec. 31.

Michelle Stermole

Director of communications, ASU Enterprise Partners