Endoscopic fetoscopy is a minimally invasive surgical procedure performed during pregnancy that allows physicians to view the fetus in-utero. Physicians use endoscopic fetoscopy to evaluate, diagnose, and treat fetal abnormalities. Physicians use an endoscope, or a thin, flexible surgical device with a light attached to its end, to perform endoscopic fetoscopy procedures. In 1954, Björn Westin performed the first endoscopic fetoscopy in Sweden. Since Westin’s initial development of the procedure, interest in endoscopic fetoscopy has grown throughout the early part of the twenty-first century. In addition, the use of endoscopy has expanded beyond fetal medicine and has been introduced to other fields of medicine such as general surgery. Endoscopic fetoscopy allows surgeons to diagnose and correct fetal abnormalities that would otherwise result in fetal death before delivery or in lifelong impairment if treatment were delayed until after delivery.

In the early 2000s, Sabata Martino and a team of researchers in Italy and Germany showed that they could reduce the symptoms of Tay-Sachs in afflicted mice by injecting them with a virus that infected their cells with a gene they lacked. Tay-Sachs disease is a fatal degenerative disorder that occurs in infants and causes rapid motor and mental impairment, leading to death at the ages of three to five. In gene therapy, researchers insert normal genes into cells that have missing or defective genes in order to correct genetic disorders. The team created a virus that coded for a specific gene missing in mice with Tay-Sachs. That missing gene is called hexosaminidase subunit alpha (HEXA). Martino and the team injected the virus into the brains of mice with Tay-Sachs in attempt to restore Hexa enzymatic function in the brain and spinal cord (central nervous system).

Bernard Sachs studied nervous system disorders in children in the United States during the nineteenth and twentieth centuries. In the late 1880s, Sachs described the fatal genetic neurological disorder called amaurotic family idiocy, later renamed Tay-Sachs disease. The disorder degrades motor skills as well as mental abilities in affected individuals. The expected lifespan of a child with Tay-Sachs is three to five years. In addition to working on Tay-Sachs disease, Sachs described other childhood neurological and developmental disorders that stem from problems with early brain development. Sachs's research in early brain development helped establish some of the physiological symptoms of hereditary neurological disorders in children, enabling doctors to diagnose the disorders earlier and to develop treatments for them.

In 1881 British opthalmologist Warren Tay made an unusual observation. He reported a cherry-red spot on the retina of a one-year-old patient, a patient who was also showing signs of progressive degeneration of the central nervous system as manifested in the child's physical and mental retardation. This cherry-red spot is a characteristic that would eventually come to be associated with metabolic neurological disorders like Sandhoff, GM-1, Niemann-Pick, and, to the credit of Tay, the lysosomal storage disorder known as Tay-Sachs disease. Tay shares the disease's title with New York neurologist Bernard Sachs, who described the cellular changes present in the disease as well as its potential for heritability, shortly after Tay's observation. Sachs also noted the higher occurrence of the disease in Jews of eastern and central European descent as well as the typical pattern of the disease, including early blindness, severe retardation, and death in early childhood.