HONG KONG (SE): Responding to the controversy surrounding He Jiankui of the Southern University of Science and Technology in Shenzhen, who claimed he switched off an HIV-related gene in twins born this November, by modifying their embryos to prevent them from contracting the disease, Father Stephen Joseph Tham, a professor of Bioethics at the Pontifical Athenaeum Regina Apostolorum, Rome, said that the life of an embryo should be respected and warned against the pursuit of high genetic quality.
 
He, a biophysics researcher, disclosed to the Associated Press in November that he had successfully edited the embryos of the twin girls whose father is an HIV carrier. The incident sparked outrage from scientists.
 
He released the result of his study at the Second International Summit on Human Genome Editing organised by the University of Hong Kong on November 28.
 
In an interview with the Diocesan Pastoral Commission for Marriage and Family, given right after attending He’s talk at the university, Father Tham remarked that since the embryos were healthy and without the virus, gene editing could not be justified by claiming it is a way to cure illness. 
 
Instead, he believes the gene editing is more likely an attempt to make people more resistant against viruses and notes that most scientists question the safety and reliability of gene editing technology at this stage of development. 
 
What is more, he noted that the embryos in question were implanted through In Vitro Fertilisation (IVF) and stressed that experiments on embryos as well as IVF are contrary to Catholic teaching, as these do not respect the life of the embryos.
 
Father Tham noted that gene editing, or CRISPR-Cas9, appeared two to three years ago and is not a complicated method. 
 
“What worries scientists is that its development is too quick,” he explained to the Kung Kao Po in another interview. He expressed concern that human beings would soon face the temptation to perfect the genes of the next generation through technology and urged people to show more respect for human lives.
 
Father Tham also noted that gene editing might not only affect the targeted gene, but also cause off-target genetic damage. In the case of the twins born in November, He Jiankui admitted in his talk that a few other genes might also also affected. 
 
Father Tham raised his concerns that if any hidden problems emerge at a later stage, the lives of the two girls will be impacted.
 
Father Tham explained that scientists are extremely careful with using gene editing for medical purposes, not only due to the concern about its safety and effectiveness, but also because of the fact that genetic problems can be passed on succeding generations. 
 
He explained that there are two kinds of gene editing, the first is somatic gene therapy, that is the transfer of genes into the somatic cells of a patient, which will not pass any genetic problems on to the next generations. However, the one used by He Jiankui can cause hereditary problems as it belongs to germline gene therapy which means DNA is transferred into the cells that produce reproductive cells, eggs or sperm, in the body.
 
Connie Chan Lai-sheung, pastoral officer with the commission, said it is wrong to use human embryos in any experiment as they are human lives and should be duly respected, even if the purpose is to help someone—a principle spelled out in Evangelium Vitae (the Gospel of Life), the apostolic exhortation of Pope John Paul II in 1985. 
 
She condemned the disposal of unused human embryos in IVF technology, as “no one can in any way permit the killing of an innocent human being, whether a fetus or an embryo, an infant or an adult.”