Skip to main content

Inherited Genetic Diseases and Scientific advances after the “The Boy in the Bubble”

Inherited Genetic Diseases and Scientific advances after the “The Boy in the Bubble”

October 2, 2023
Dr. Lana du Plessis
October 2, 2023
Dr. Lana du Plessis

An extraordinary boy enthralled the globe at the start of the 1970s. Years later, his tale is still developing in remarkable ways.

When David Vetter was born in September 1971 at Texas Children’s Hospital in Houston, he was diagnosed with Severe Combined Immunodeficiency (SCID), which was practically a death sentence. In fact, his 7-month-old SCID (Severe Combined Immune Deficiency) brother had passed away from the same disease just a year earlier. The disease’s most prevalent form, which affects exclusively boys (though girls can be carriers) and is defined by a fatal X chromosomal abnormality, was present in both youngsters.

Being diagnosed with SCID *(pronounced as “skid”) meant that he had no working immune system from birth. He could have died from any stray germs inhaled by breathing regular air or from touching someone else. Depending on which study one believes, one in 100,000 to one in 50,000 live births are claimed to be affected by SCID, which is a hereditary condition. In the United States, where over four million infants were born in 2014, that equates to 40 to 80 SCID infants each year.

His doctors tried a brand-new bone marrow procedure in October 1983 that didn’t demand a perfect blood match. The donor was Katherine Vetter, David’s four-year-old sister. Given the close genetic match between siblings meant that she was his best hope for a cure. The process appeared to work initially. However, the Epstein-Barr virus was dormant and undiagnosed in Katherine’s bone marrow. It turned out to be fatal, igniting malignant tumors that overran David’s body and he passed away shortly afterwards.

The epitaph on David Phillip Vetter’s gravestone correctly observes that “he never touched the world.” How could he have?

Since then, medical research has advanced to the point where, when performed within a baby’s first three months of life, a blood-forming stem cell transplant is typically successful in treating SCID. The ability to diagnose SCID early—even in utero—has considerably increased.

The success of bone marrow transplantation after birth is, however, constrained by the lack of suitable donors, disease-related harm already done to the child, the child’s immune system rejecting the donor cells, and, in some cases, graft-versus-host disease (GVHD), in which the donor cells reject the baby’s tissue.

In some cases of genetically inherited diseases, prenatal intervention may be considered. Given that the genetic disorder causes ongoing damage to the fetus which can be avoided through earlier treatment. As the treatment will require blood-forming stem cell transplantation, it is preferable to consider intervention prior to birth.

Fast-forward to the present

Today, fetal DNA collected in the first trimester can be used to correctly diagnose a wide range of inherited genetic illnesses in the early stages of development. Most often, testing is carried out because the patient is known to be a carrier of the ailment, or because the condition is known from family history, or because the patient and their partner have been recognized as carriers. In many inherited diseases blood-forming stem cell transplantation from a donor can be used to treat these diseases, either prior to birth or immediately thereafter. Options for treatment vary according to the condition.

Gene therapy, which is still in the clinical testing phase, might be a new weapon in the medical armory. A healthy gene is introduced into a patient’s system using a safe virus to replace a damaged gene that is the cause of illnesses like immune insufficiency, sickle cell anemia, and hemophilia. The curative potential of gene therapy is generally acknowledged. But since it was first used in 1990, it has had both successes and setbacks in equal measure, and the Food and Drug Administration is yet to give it the thumbs up.

The following Inherited Genetic Diseases might be treated in-utero with normal blood-forming stem cell transplantation i.e. Hemoglobinopathies, Immunodeficiency Diseases, Inborn Errors of Metabolism, Mucopolysaccharidoses, Mucolipidoses, Osteopetrosis, Diamond-Blackfan syndrome, and Fanconi anemia. Current gene-editing stem cell therapy for sickle cell disease awaits FDA approval towards the end of 2023. The use of Engineered Stem Cells for transplant has not been fully approved in any of the other diseases.

The scientific advances provide David’s family a reason to celebrate every day, especially on his birthday, even if the loss of a child never goes away. Because of David, it is now possible to screen newborns for many genetically inherited diseases as well as immunological illnesses. There are approximately 400 immunodeficiency conditions that are currently treatable before a patient contracts a potentially fatal infection. Since David was the first patient, numerous more can now be treated with blood-forming stem cell transplantation, one of the greatest scientific breakthroughs of our time.

Share this article with friends and family