In the 1987 sci-fi movie Innerspace produced (though not directed) by Steven Spielberg, a man was miniaturized and mistakenly injected into the body of another living person. The desperate Lilliput tried to manipulate the internal biological functions of his host in a bid to escape the predicament. Definitely the stuff of fiction, but science is catching up fast – in a way!
Ophthalmologists at the Casey Eye Institute in Portland, U.S, have recently transformed a harmless virus into a gene-editing tool and injected it into the eye of a visually impaired patient. Inside, the tool is expected to edit and rectify the abnormal gene that caused the blindness and recover vision.
The patient suffers from arare genetic conditioncalled LeberCongenital Amaurosis in which light-sensing cells in the retina gradually stop functioning. In most cases this eventually leads to total or near-total blindness. Genetic engineering was thought to be a possible solution.
The CRISPR gene-editing technique has been revolutionizing treatment for genetic conditionsthrough advanced ways of rewriting the DNA. It has already been used with considerable success in treating beta-thalassemia, sickle cell anaemia, andcertain types of cancer. Yet, for all these cases, cells extracted from the patient’s body were altered in the laboratory, and then reintroduced in the body to perform their intended mission. But the Portland eye surgeons applied the CRISPR technique to directly edit genes on a DNA within the patient’s body. It is the first attempt of its kind.
The process is apparently simple. As a first step, a benign virus was programmed to convey the CRISPR gene-editing instructions under the retina. Next, three drops of fluid containing billons of pre-programmed virus were injected behind the eye through incisions. Doctors expect the virus to get infused into the eye where the CRISPR editing instructions would eliminate the mutation that caused a defect in the CEP290 gene.That may restore production of a crucial protein to prevent degeneration of retinal cells and renew some damaged cells too – bringing back partial vision.
Being a pioneering attempt, no one is yet sure of the results. It would take a couple of months, if not more, to identify any real improvement. But the doctors are optimistic, and any amount of success would be a huge boost to this novel procedure, which will then be gradually employed to engineer other abnormal genes – all within the body – without the need of elaborate laboratory apparatus.