Scientists make breakthrough in down syndrome treatment in Japan

Scientists from the Mie University Graduate School of Medicine in Japan have made progress in treating Down syndrome through genomic modification, according to an article published by PNAS Nexus, Report informs.

The experts have managed to remove the extra copy of chromosome that causes this genetic disorder.

Down syndrome (DS) is a genetic disorder caused by the presence of an extra copy of human chromosome 21 (HSA21). It is the most common viable chromosomal abnormality, occurring in ∼1 in 700 live births. Extensive research has been conducted to elucidate the clinical features, genetic causes, and cellular characteristics of DS. These studies have been aided by the development of innovative animal models and advancements in prenatal diagnostic techniques, such as preimplantation genetic testing for aneuploidy. Despite these significant strides, a relative paucity of research has addressed the fundamental cause of DS. Specifically, strategies are required to eliminate the extra chromosome from trisomic cells.

A team led by Ryotaro Hashizume used CRISPR-Cas9 to remove the extra chromosome in cell lines derived from pluripotent stem cells and skin fibroblasts.

The researchers were able to precisely identify and remove the duplicated chromosome while maintaining one copy from each parent. Suppression of DNA repair mechanisms increased the efficiency of extra chromosome removal. After the extra chromosome was removed, gene expression and cellular functions returned to normal levels.

However, as the authors note, the method is not yet ready for use in living organisms. The current technology can accidentally damage other chromosomes, which requires further improvement.

Although clinical application is still far away, the research represents an important step forward in finding ways to treat genetic diseases. Scientists hope that further developments will allow adapting the method for safe use in medicine.