Gene-edited ba­bies born … now what?

Houston Chronicle - - FROM THE COVER - By Christo­pher Thomas Scott Scott is the as­so­ciate di­rec­tor of health pol­icy at the Cen­ter for Med­i­cal Ethics and Health Pol­icy at Bay­lor Col­lege of Medicine.

“Baby #3 on the way.”

A short note from a col­league in Hong Kong at­tend­ing the Na­tional Acad­e­mies of Sci­ence, En­gi­neer­ing and Medicine’s sec­ond in­ter­na­tional sum­mit on hu­man genome edit­ing hit me like a thun­der­clap.

Dr. He Jiankui was on stage. Days ear­lier, he claimed that he had mod­i­fied the genes of two em­bryos and im­planted them in a woman, who gave birth to twins. One of the ba­bies had genes edited to make it po­ten­tially re­sis­tant to HIV.

Then, Dr. He, a Chi­nese sci­en­tist who had stud­ied in the U.S., dropped the other shoe: a third ge­net­i­cally mod­i­fied baby might be on the way. Three de­signer ba­bies — for­merly the stuff of sci­ence fic­tion — would soon tod­dle among us.

Crit­i­cism from the in­ter­na­tional sci­en­tific and bioethics com­mu­ni­ties was swift. The over­whelm­ing con­clu­sion was that Dr. He’s pro­ce­dure was de­cep­tive, ap­peared to vi­o­late Chi­nese law, flouted in­ter­na­tional eth­i­cal norms and put the ba­bies at phys­i­cal risk. Dr. He’s tech­nique can cause chro­mo­so­mal re­arrange­ments and mu­ta­tions, which can be can­cer­ous. Chang­ing one gene can af­fect other genes and can lead to in­creased sus­cep­ti­bil­ity to vi­ral in­fec­tions.

More­over, Dr. He’s pro­ce­dure didn’t work per­fectly. The sec­ond child’s genome was in­com­pletely edited: only one gene was cut. Dr. He stated that the chil­dren ap­peared to be cel­lu­lar mo­saics, or ad­mix­tures of edited and unedited cells.

It’s un­clear what in­ter­gen­er­a­tional ef­fects Dr. He’s snip­ping and cut­ting have wrought. But the chil­dren will carry these changes in their genome for the rest of their lives. The changes will be in­her­ited by their chil­dren, and their chil­dren’s chil­dren. The pro­ce­dure — if proved to be the real thing — amounted to un­eth­i­cal hu­man ex­per­i­men­ta­tion.

Nev­er­the­less, calls for ban­ning re­search sim­ply be­cause of this ex­per­i­ment would set back the con­sid­er­able progress we have made in the genome edit­ing field and bury the prom­ise of a po­ten­tially pow­er­ful ther­a­peu­tic tech­nol­ogy. We should not stop re­search that will tell us whether that re­search is safe and ef­fec­tive. But the ap­pear­ance of these de­signer ba­bies has brought three ma­jor ethics and pol­icy ques­tions into sharp fo­cus.

The first ques­tion de­mands that we step back and con­sider rec­om­men­da­tions for CRISPR, which Dr. He used for this pro­ce­dure, and other tech­nolo­gies for germline mod­i­fi­ca­tion. In 2017, sci­en­tists, ethi­cists and other ex­perts opened the door to us­ing CRISPR for just this kind of need. Child­hood cancer, Tay-Sachs dis­ease, ALS and cys­tic fi­bro­sis com­monly ap­pear as tar­gets for gene edit­ing. From an ethics and pub­lic health per­spec­tive, if we could safely use genome edit­ing to banish a deadly dis­ease such as Hunt­ing­ton’s from the world, why wouldn’t we?

Sec­ond, CRISPR has es­caped the shack­les that tend to hold com­pli­cated tech­nolo­gies in the lab­o­ra­to­ries of highly skilled molec­u­lar and cel­lu­lar bi­ol­o­gists. CRISPR is easy to use and cheap. Dr. He is a physi­cist, as is his U.S. col­lab­o­ra­tor and men­tor at Rice Univer­sity, Dr. Michael Deem. And since Dr. He re­ceived some of his train­ing in the U.S. — in­clud­ing at Stan­ford Univer­sity — the les­son is that the Chi­nese CRISPR ex­per­i­ment isn’t ex­clu­sively China’s prob­lem. It’s a global co­nun­drum, and the world can’t wait for the slow pace of eth­i­cal reck­on­ing that is symp­to­matic of groups of ex­perts as they de­lib­er­ate about what should be done to­mor­row. To­mor­row has ar­rived, and this event must gal­va­nize in­ter­na­tional ac­tion in the sci­en­tific com­mu­nity now.

Third, Dr. He’s ex­per­i­ment — whether he in­tended it or not — touches on a largely un­re­solved di­men­sion of sci­ence pol­icy. Straight­for­ward ap­pli­ca­tions of genome edit­ing could erad­i­cate hu­man dis­ease. How­ever, Dr. He’s ex­per­i­ment in­volved ge­net­i­cally con­fer­ring dis­ease preven­tion to a hu­man em­bryo. Should we use CRISPR to, say, in­oc­u­late hu­mankind against the rav­ages of ag­ing? Should we use the tech­nol­ogy to help us to keep our mus­cle toned in our eighth and ninth decades of life? The bound­aries be­tween med­i­cal uses, pre­ven­ta­tive uses and uses for hu­man en­hance­ment are not so clear.

On this last point, ev­ery in­ter­na­tional group agrees: As CRISPR be­longs to all of us, we must fully en­gage cit­i­zens in an ef­fort to un­der­stand pub­lic opin­ion be­fore we can re­spon­si­bly adopt these ground­break­ing dis­cov­er­ies.

Once we have suf­fi­ciently ad­dressed these three ques­tions, it might then be time to call for CRISPR baby num­ber four.

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