Medical technologies are coming that can cure or prevent terrible diseases, or give people superhuman health and intelligence through gene editing or bio-mechanical brain implants. Many Americans, however, fear a medical treatment gap will eventually grow between the wealthy who can afford these experimental, life-saving technologies and the poor who cannot, according to a survey conducted by the Pew Research Center.

Pew on Tuesday published a survey of more than 4,700 U.S. adults, more than two-thirds of whom expressed worry about the potential to one day enhance human potential using gene editing at birth, cybernetic brain chip implants or synthetic blood to enhance stamina and performance. Only a third of respondents were somewhat or very enthusiastic about the chance to use these enhancements.

Gene editing to improve a baby’s health was the most appealing option suggested, however, as 48 percent of people said they would consider the treatment that is focused on disease-prevention, not augmenting abilities.

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Such technologies are not available in today’s hospitals but exist in some stage of research, so the Pew researchers stated their goal was to determine “where, if at all, the public might 'draw the line’ on human enhancements and the possibilities they could bring to society.”

“Whatever appeal these ideas may have, they also raise fundamental questions about what it means to be human,” according to the study. “As new scientific and technological breakthroughs arise, so do questions about whether such developments move beyond limits set by God, nature or reason.”

Ethical concerns drove more than 70 percent of respondents to predict that these technologies will be available to patients before they are fully understood or tested. The same 70 percent of respondents added the availability of the potentially expensive new treatments to enhance strength, longevity or intelligence would also deepen the digital divide between rich and poor.

Religion impacted respondents' concerns about whether human enhancement is unethically meddling with nature. Highly religious Americans expressed these worries more than 60 percent of the time, while people with a stated low commitment to religion expressed such doubts about 30 percent of the time.

Using technology to restore someone’s health and body seemed appropriate among respondents, and 62 percent of them did not have a problem with the ethics of cosmetic surgery. Respondents feared, however, that using new technologies to enhance someone beyond their natural limits would make them superior to those who did not have them.

Gene editing at birth would breed arrogant children, according to 53 percent of people surveyed, while 71 percent feared a false sense of superiority among people with brain implants to boost intelligence, and 63 percent said the same of people who were enhanced with synthetic super-blood.

These fears are well established in science fiction. Gene Roddenberry, creator of the "Star Trek" universe – which predicted things like tablets and cell phones – also portended a World War III that features wars fought by genetically enhanced people on a sort of eugenics jihad. The film “Elysium” also depicted a future where the wealthiest 1 percent have access to machines that can cure cancer despite global poverty. An elitist class structure also develops among a fictional society that prizes genetic engineering in the film “Gattaca.”

Examples of research into genetic enhancement include the Clustered Regularly Interspaced Short Palindromic Repeats gene editing tool, also known as CRISPR-Cas9, which could one day modify genes to cure or prevent autism, HIV or cancer.