Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
02 August 2022 | Story Leonie Bolleurs | Photo Leonie Bolleurs
Alistair Naidoo, second-year master’s student in Conservation Genetics and full-time technician in the Department of Genetics; Prof Paul Grobler, Head of the Department of Genetics; Prof Gordon Luikart; and Hannah Janse van Vuuren, third-year master’s student in Conservation Genetics.

It is an important and exciting time to be doing research in conservation genetics. This is according to Prof Gordon Luikart, Professor of Conservation Ecology and Genetics at the Flathead Lake Bio Station at the University of Montana in the United States. 

Prof Luikart, whose primary research focus is the application of genetics to the conservation of natural and managed populations, recently delivered a lecture, The Expanding Role of Genetics/omics in Wildlife Research and Conservation, on the Bloemfontein Campus of the University of the Free State (UFS). The lecture, hosted by the Department of Genetics, was attended by a group of students and lecturers in conservation and a number of related fields. 

He is one of the leading scientists in the field of conservation genetics, including integration of genomics in conservation projects. He is also co-author of the textbook Conservation and the Genomics of populations – the current prescribed textbook for GENE3744.

Species threatened with extinction

In 2008, the International Union for Conservation of Nature (IUCN) stated that approximately 10-20% of all vertebrate and plant species are threatened with extinction over the next few decades. In 1984, American biologist Edward O Wilson also said that it will take millions of years to correct the ongoing loss of genetics and species diversity caused by the destruction of natural habitats. “This is the folly our descendants are least likely to forgive us.”

Prof Luikart is of the opinion that genetics has enormous potential to help manage wildlife and prevent extirpation. “My research works to realise this potential and help wildlife managers conserve populations and ecosystems,” he says. 

Conservation managers and biologists have understood the risks of inbreeding for more than 100 years. In his lecture, one of the aspects of genetic conservation he focused on, was the negative effects of inbreeding and how this can be reversed using genetic rescue. 

With the genetic rescue study, they found that the gene flow into recently isolated populations can increase individual fitness and population growth. He proposed that conservation managers should consider genetic principles and rescue as practical and important tools. 

Prof Luikart also provided a list of information that can be retrieved from molecular genetic data to help conservation managers. This includes intel on census and effective population size, gene flow and dispersal, local adaptation and selection, forensics, genetic identification and law enforcement, and disease ecology and transmission. 

Non-invasive genetic monitoring

In terms of detecting gene flow, he focused on a study about non-invasive genetic monitoring that was conducted in the Yellowstone Park. Prof Luikart and a group of students collected the shed hair and faeces of the grizzly bear, obtained from trees and hair traps, which were used as a source of DNA. 

They established, for instance, that inbreeding depression is more common and stronger than previously thought in natural populations. Genetic monitoring, using non-invasive methods as described, has been found to be an effective tool that conservation managers should consider for detecting inbreeding and loss of genome-wide variation.

His research on the bighorn sheep, the alpine ibex, and the black bear informed most of the findings he discussed during his lecture.

News Archive

UFS study on cell development in top international science journal
2008-09-16

A study from the University of the Free State (UFS) on how the change in the packaging of DNA with cell development influenced the expression of genes, will be published in this week’s early edition of the prestigious international, peer-reviewed science journal, the Proceeding of the National Academy of Sciences of the USA (PNAS).

The PNAS journal has an impact factor of 10, which means that studies published in the journal are, on average, referred to by ten other scientific studies in a two year period. The South African Journal of Science, by comparison, has an impact factor of 0.7.

The UFS study, funded by the Wellcome Trust and the National Research Foundation (NRF), looked at how the change in the packaging of DNA with cell development influenced the expression of genes. It is very relevant to research on stem cells, an area of medicine that studies the possible use of undifferentiated cells to replace damaged tissue.

Prof. Hugh Patterton, of the Department of Microbial, Biochemical and Food Biotechnology at the UFS, who led the study, said: "We are extremely proud of this study. It was conceived in South Africa, it was performed in South Africa, the data were analysed in South Africa, and it was published from South Africa."

When a gene is expressed, the information encoded in the gene is used to manufacture a specific protein. In eukaryotes, which include humans, there is approximately 1m of DNA, containing the genes, in every cell. This length of DNA has to fit into a cell nucleus with a diameter of only about 10 micrometer. In order to fit the DNA into such a small volume, eukaryotic cells wrap their DNA onto successive protein balls, termed nucleosomes. Strings of nucleosomes, resembling a bead of pearls, is folded into a helix to form a chromatin fiber. The study from the UFS investigated how the binding of a specific protein, termed a linker histone, that binds to the length of DNA between nucleosomes, influenced the formation of the chromatin fiber and also the activity of genes.

"We found that the linker histone bound to chromatin in yeast, which we use as a model eukaryote, under conditions where virtually all the genes in the organism were inactive. It was widely believed that the binding of the linker histone caused the inactivation of genes. We studied the relationship between the amount of linker histone bound in the vicinity of each gene and the expression of that gene for all the genes in yeast, using genomic techniques. We made the surprising discovery that even through the linker histone preferentially bound to genes under conditions where the genes were shut off, this inactivation of genes was not caused by the binding of the linker histone and folding of the chromatin,” said Prof. Patterton.

He said: “Instead our data strongly suggested that the observed anti-correlation was due to the movement of enzymes along the DNA molecule, involved in processing the information in genes for the eventual manufacture of proteins. This movement of enzymes displaced the linker histones from the DNA. This finding now requires a rethink on aspects of how packaging of DNA influences gene activity."

Prof. Patterton said that his research group, using the Facility for Genomics and Proteomics as well as the Bioinformatics Node at the UFS, was currently busy with follow-up studies to understand how other proteins in nucleosomes affected the activities of genes, as well as with projects to understand how chemicals found in red wine and in green tea extended lifespan. "We are certainly having a marvelous time trying to understand the fundamental mechanisms of life, and the UFS is an exciting place to be if one was interested in studying life at the level of molecules," he said.


Media Release
Issued by: Lacea Loader
Assistant Director: Media Liaison
Tel: 051 401 2584
Cell: 083 645 2454
E-mail: loaderl.stg@ufs.ac.za  
18 September 2008
 

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept