Le Prader-Willi syndrome (PWS) is a disease characterized at birth by a lack of muscle tone (hypotonia), lower than normal weight and height, and difficulty feeding, followed by early obesity associated with excessive food during childhood. According to the prevalence of this disease due to a genetic abnormality is estimated at 1 per 50 inhabitants. The genes involved are located on a part du chromosome 15. In addition to the sex chromosomes, for each pair of chromosomes, one copy is inherited from the mother and the other from the father.
Under normal circumstances, genes in this region are inactive on maternal chromosome 15, but active on paternal chromosome 15. But in infants with PWS, this region of the paternal chromosome is inactive or missing. Researchers at Duke University, in the United States, are on the promising track of a treatment, since they have succeeded in developing a drug capable of activating this part on the maternal copy of the gene in sick mice.
Mice grow better and live longer
The latter developed poorly, like infants with PWS, and did not survive. Medication called UNC0642 targets maternal genes because unlike paternal genes, these are routinely available in patients with PWS. With this treatment, the treated mice exhibited growth and weight gain higher than untreated mice. In addition, 15% of them survived to adulthood without showing serious side effects.
The medicine works by inhibiting the activity of a protein called G9a, which, along with other proteins, assembles maternal genes tightly in the chromosome. While overall, the study shows the drug to show promise, researchers believe more studies are still needed. They want to assess its effects on other symptoms of the disease that appear later, around the age of 2 years, such as compulsive overwork and obesity.