Latest way to beat infertility? Try ‘three-parent babies’
For $US50,000 and up, Dr. John Zhang is offering women in their 40s a “solution” for age-related infertility — swapping chromosomes between two women’s eggs, resulting in a child with, technically speaking, three genetic parents.
Some of the hopeful mothers-tobe he’s screening are in Canada.
Zhang, who spearheaded the delivery of the world’s first baby born last year from his controversial DNA-blending technique, is now preparing to offer the procedure to older women desperate for their own biologically related babies. “We hope to begin cases within the next few weeks,” he said in an email to the Post. Canadian women are among those being considered for the revolutionary — and some say hugely ethically objectionable — procedure.
The criteria are straightforward enough: the women have to be aged 42 to 47, they must have failed at least two rounds of traditional in vitro fertilization and still have their periods. They also have to be prepared to pay US$50,00 to $100,000.
Zhang’s “three-parent baby” procedure was originally presented as a noble goal to prevent women from transmitting devastating mitochondrial diseases to their children.
However, the Manhattan-based, Chinese-born scientist is now also targeting the lucrative fertility industry, promising to “reverse the effects of age” on human eggs.
His procedure, known as spindle nuclear transfer, involves removing the nucleus, which contains the majority of maternal DNA, from one woman’s eggs and injecting it into the egg of a younger donor.
The donor egg, stripped of its own nucleus, has what the older egg doesn’t: A more youthful mitochondria. Mitochondria work like miniature power plants, supplying energy to virtually every cell in the body. Evidence suggests that as women age, the energy-output of the mitochondria decreases, meaning less power to fuel cell division after fertilization, making it harder to achieve a successful pregnancy.
The new, “reconstituted” egg, which conceivably could be decades younger in age than the woman herself, is fertilized with the male partner’s sperm, the resulting embryo transferred to the woman’s womb and, if all goes according to plan, a healthy baby is born.
According to Zhang’s new startup, “Darwin Life,” as reported by Technology Review last week, successfully swapping its nuclear contents turns the donor egg into a 98.9-percent genetic match to the mother (the remaining 1.1 per cent of genetic material coming from the other woman).
Last September, the world’s first baby conceived via spindle nuclear transfer was born to a couple from Jordan. The mother was a carrier of a lethal, progressive neurological disorder caused by a mutation in her mitochondrial DNA that led to the loss of two other children. Zhang performed the egg collection and mitochondrial replacement in the U.S. but the actual embryo transfer itself was performed in Mexico, circumventing American laws effectively banning the procedure in the U.S.
Details of the work — backed by privately funded research — were only revealed this past April.