Researchers from Carnegie Mellon University devised a gene editing technique that might treat genetic conditions during fetal development.
According to Center for Disease Control and Prevention (CDC) around 8 million children are born each year with severe genetic disorders or birth defects. These genetic disorders can be detected during pregnancy using amniocentesis. However, no treatment is available to correct these genetic conditions before birth. Now researchers from Carnegie Mellon University and Yale University devised a gene editing technique to treat genetic condition in a mouse model. The research was published in the journal Nature Communications on June 26, 2018.
The method is a peptide nucleic acid-based gene editing technique. It was earlier used to cure a genetic blood disorder called beta thalassemia, which results in reduced production of hemoglobin. Peptide nucleic acids (PNA) are synthetic molecules that combine a synthetic protein backbone with the nucleobases found in DNA and RNA. An FDA-approved nanoparticle delivers PNA molecules paired with donor DNA to the site of a genetic mutation. This PNA-DNA complex identifies a designated mutation and the PNA molecule binds to the DNA and unzips its two strands. The donor DNA binds with the faulty DNA and spurs the cell’s DNA repair pathways into action, allowing it to correct the error. The method was similar to amniocentesis injecting the PNA complex into the amniotic fluid of pregnant mice whose fetuses carried a mutation in the beta-globin gene that causes beta thalassemia. A single injection of PNA during gestation was able to correct 6 percent of the mutations, which in turn caused drastic improvements in the mice’s symptoms of beta thalassemia. Mice treated using PNA while in utero showed normal levels of hemoglobin with increased survival rates. No off- target effects were noticed from the treatment. The researchers stated that the technique is expected to achieve even higher success rates with multiple times administration during gestation.