Embryos won’t use anything else but parent's genes

Extending human genome seems to be impossible

https://www.statnews.com/2017/08/02/crispr-designer-babies/

Excerpt: "Creating “designer babies” with a revolutionary new genome-editing technique would be extremely difficult, according to the first U.S. experiment that tried to replace a disease-causing gene in a viable human embryo.

Partial results of the study had leaked out last week, ahead of its publication in Nature on Wednesday, stirring critics’ fears that genes for desired traits — from HIV resistance to strong muscles — might soon be easily slipped into embryos. In fact, the researchers found the opposite: They were unable to insert a lab-made gene.

Biologist Shoukhrat Mitalipov of Oregon Health and Science University, who led the first-of-its-kind experiment, described the key result as “very surprising” and “dramatic.”
 

The “external DNA” provided to fertilized human eggs developing in a lab dish “was never used,” he told STAT. The scientists excised a mutated, heart-disease-causing gene from the embryos — a gene that came from sperm used to create them through in vitro fertilization — and supplied them with a healthy replacement. But every single one of the 112 embryos ignored it. Instead, they copied the healthy gene from their mother and incorporated that into their genome to replace the father’s.

“This is the main finding from our study,” Mitalipov said: Embryos’ natural preference for a parent’s gene “is very strong, and they won’t use anything else.”

The discovery suggests that opportunities for disease prevention are more limited than scientists assumed and that enhancement — giving a days-old embryo “better” genes — is unlikely to succeed, at least with current methods. Genetic tinkering can, however, eliminate a “bad” gene that an embryo got from one parent and replace it with a “good” gene from the other parent. And the experiment showed for the first time in a large number of embryos that this can be done efficiently and without harming other genes."

My comment: Genes are no drivers or controllers. Gene sequences don't determine traits. Scientists are not able to extend human genome by inserting more genetic material into embryonic cells. But due to rapid degeneration of the human genome, scientists are in a hurry to develop accurate gene editing techniques, by which they can remove faulty sections by letting the cell repair damages or by inserting healthy genetic material from parent's genome. Interesting is that the embryonic cells don't accept insertion of external genes. So, scientists can forget the idea of designer babies. And they can forget the idea of human induced evolution.