CONTACT: Aseem Ansari, (608) 239-7445, azansari@wisc.edu;
Natalie Racine, nracine@wisc.edu
DOWNLOAD PHOTOS: https://uwmadison.box.com/v/ansari-ataxia
MADISON – Using a molecule designed to overcome a roadblock formed by a common type of genetic flaw, researchers at the University of Wisconsin-Madison have made progress towards novel molecular treatments for Friedreich’s ataxia – a rare but fatal disorder – in the laboratory dish and in animals.
Friedreich’s, like at least 40 other genetic diseases, is caused by stretches of repetitive DNA that prevent protein from forming correctly.
The repeats can contain hundreds of identical, short sequences of DNA (such as GAAGAAGAAGAA …). In some diseases, including Friedreich’s, the repeats become roadblocks to cellular machines that decode the gene and start making the protein that the cell needs. In other diseases, such as the neurological condition Huntington’s, the repeats can result in excess protein, which itself can become toxic.
In research reported this week in the journal Science, Aseem Ansari, a professor of biochemistry and genomics at UW-Madison, and colleagues showed that their “molecular prosthesis” can help cellular machinery overcome the blockade posed by the repeats in Friedreich’s ataxia.
One component of the prosthesis locates the repeats, then the second helps the cellular machinery soldier past the repeats to properly decode the gene.
Friedreich’s appears in only one American in 50,000, but it’s fatal and untreatable, says Ansari. “These kids accumulate repeats in a gene for a protein called frataxin that mitochondria, the cell’s powerhouse, need to process energy. Without frataxin, tissues that use the most energy get hurt first: the brain, heart and pancreas.”
As early as age 5, movement is impaired “because the brain does not have the energy it needs and it also accumulates DNA damage,” says Ansari, who has a joint appointment with the Genome Center of Wisconsin at UW-Madison. “Most young people with Friedreich’s develop severe heart problems and are wheelchair-bound, but the disease is so rare that few drug companies invest in it.”
In the Ansari group, Graham Erwin, Matthew Grieshop and Asfa Ali formed a team that designed and created the prototype molecule, and also orchestrated collaboration with colleagues at UW-Madison, the pharmaceutical firm Novartis, and a leading medical center in India.
READ MORE AT https://news.wisc.edu/designer-molecule-points-to-treatment-for-diseases-caused-by-dna-repeats/
