The absence of the gene affects the animals’ biological clocks, inducing sleep problems, nighttime hyperactivity, hormonal disorders, depression and schizophrenia.
Five cloned monkeys have been born with genes that were edited to cause sleep disorder, a team of researchers from the Institute of Neuroscience at the Chinese Academy of Sciences in Shanghai announced Wednesday.
"Circadian rhythm disorder is related to many human diseases, such as sleep disorders, diabetes mellitus, cancer and neurodegenerative diseases, which means that our genetically edited monkeys could be used to study the pathogenesis of the disease, as well as therapeutic treatments," Hung Chun Chang, lead researcher, explained.
The Chinese scientists explained that they used a genetic editing tool known as CRISPR/Cas9 to knock out a gene known as BMAL1 from healthy embryos.
The technique was presented, as a new tool for biomedical research, in articles published in China's National Science Review.
The absence of the gene affects the operation of the animals’ biological clocks, which induces diseases such as sleep problems, nighttime hyperactivity, hormonal disorders, depression and schizophrenia.
All five macaques were born with identical genes, which include the mutation.
In the future, "personalized" genetically modified monkeys could be obtained to study other human diseases.
"Our approach is to perform gene editing on fertilized embryos to first generate a group of gene-edited monkeys and then select a monkey that exhibits the correct gene-editing and most severe disease phenotypes as the donor monkey for cloning," scientist Qiang Sun said, stressing that "this approach to cloning edited monkeys could be used to generate a variety of monkey models for genetic diseases, including many brain diseases, as well as immune and metabolic disorders and cancer."
China is the only country capable of cloning primates so far, the South China Morning Post stated, recalling that other scientists around the world have tried unsuccessfully to achieve this feat for decades.