A team of scientists from Chungnam National University (CNU) in South Korea have recently created two beagle dogs from cloned skin cells altered by gene-editing technologies. The researchers hope that this technique could be used more broadly in the near future to eliminate disease-causing mutations from pedigree dog breeds.
Because of years of inbreeding, pedigree dogs are frequently susceptible to genetic diseases. For instance, some cocker spaniels are known to have brains too large for their skulls, while boxers are often suffering from epilepsy. By using a gene-editing tool called CRISPR-Cas9, the CNU scientists created the beagles by first editing skin cells to mutate a gene (DJ-1) that is associated with degenerative diseases such as Parkinson’s. They then placed these gene-edited skin cells next to egg cells whose DNA had been removed, and fused them together by using short pulses of electricity. Through this technique, a total of 68 embryos were created and implanted into six surrogate mothers, resulting in two puppies.
The two cloned beagles are now 22 months old and do not show signs of any abnormalities. “DJ-1 KO dogs show partial or complete repression of target gene expression,” the study authors reported. “This technology can be used in further studies to produce pathogenic gene-corrected or disease-modelling dogs.” However, since the diseases linked to the DJ-1 gene are age-related, it is still too early to tell whether the dogs will experience any degenerative diseases as they get older.
Although the first human trials of CRISPR therapies have already been initiated, and scientists hope they are on the brink of reaching the clinics, many researchers remain skeptical about these developments. According to some scholars, gene-editing tools could potentially cause unwanted mutations that may prove dangerous. Others worry that this groundbreaking technology could lead to the creation of “designer babies,” by allowing parents to choose their children’s hair color, height, or even traits such as intelligence. However, regardless of these critical stances, most scientists remain hopeful that these methods could ease the burden of disease in many animals, including humans.
The study is published in the journal BMC Biotechnology.