Following the birth in London of the first genetically screened baby without breast cancer gene in January this year, the British medical community is expected to promote a more advanced gene analysis technology during the year. It can screen out almost all of the embryos. Existing genetic diseases create "disease-free babies."
According to reports, the technology is called "karyomapping". Its principle is to compare the DNA samples of embryos with parents and close relatives and screen the genetic disease genes by drawing a phylogenetic tree.
In operation, the scientists will take out DNA samples of parents and close relatives, usually children with the disease, compare the DNA of the embryos using slicing techniques, and then plot how the DNA of the genetic material from the four grandparents is arranged. , to determine whether the embryo inherited the stain containing the wrong gene.
At present, the commonly used genetic screening technique, preimplantation genetic diagnosis (PGD), removes cells one by one when the embryo develops to eight cells, and then screens each cell for hereditary diseases and finds one. Cells with harmful genes are returned to the uterus.
Scientists point out that compared to the two technologies, the PGD technology is time consuming, expensive, and can detect only 2% of the 1,500 genetic diseases, while the "nuclear mapping" technology costs about 2,500 pounds, which can take a very short time. Almost all genetic disease genes were detected within.
The only genetic condition that the "nuclear mapping" technique cannot detect is random gene mutations. Even so, this technology is superior to the traditional PGD detection technology. The "nuclear mapping" technique can also detect abnormal chromosomes that may cause embryonic death to increase the success rate of in vitro fertilization.
At present, scientists at the London Bridge Center in the United Kingdom have used the “nuclear mapping†technique to test 100% of embryos carrying cystic fibrosis (a hereditary pancreatic disease) genetic gene. The relevant British authorities have allowed this technique. Entering the clinical trial stage, it is expected to serve couples in need by the end of this year.
Like PGD technology, "nuclear mapping" technology has also raised ethical controversy about "customized babies." In response, Prof. Tony Rutherford, chairman of the British Population Center, said that concerns about “customized babies†existed before new technologies were created and that relevant authorities in the UK would strictly limit and supervise the application of new technologies. (Tianle)