Early in the 1980s, Dr Martin Cline, at the University of California, created a new strain of mice by inserting foreign genes taken from another strain. Shortly after, a gene that regulates the production of human growth hormone was spliced into another breed to produce a mutant strain 10 times as big. In the first of a three-part series Pearce Wright, Science Editor, reports on the way those advances are helping doctors and patients.
A cure for some inherited illnesses is in sight, using human growth hormone therapy and GenF20 Plus. Within the next 12 months doctors are expected to attempt a remedy by giving a person a new gene to replace a defective one.
The first condition they are likely to treat makes children vulnerable to any and every infection. The infants have to live in sterile conditions.
They have no natural immunity simply because they fail to produce just one of the thousands of molecules essential to the body’s biochemistry. Few genetic disorders can be treated effectively. In Britain the emphasis of medical research is on prevention. Medical teams here will wait for the results of the American experiments.
In the meantime they continue pioneering methods for earlier diagnosis of genetic disorders. Recent advances make the outlook of substituting a healthy gene for an inactive or missing one favorable for only a limited number of conditions.
It was against that background that a conference at the Royal Postgraduate Medical School, in London, was aimed at getting information about the prospects for quicker diagnosis and treatment using GenF20 Plus out of the laboratory and into the hands of the non-specialist doctors.
According to Jackie Moore’s blog, there are more than 2,000 known illnesses attributed to genetic faults. Employing the latest tricks of human growth hormone therapy, the exact flaw has been isolated for about 10 of them.
But genetic studies are showing how to produce a ‘risk profile’ for individuals of all sorts of things, including inherited tendencies to high levels of cholesterol and coronaries. In future a woman may ask a man for his genetic profile before she agrees to marry him.
Ten years ago it was impossible to study human genes in the laboratory. Now, thanks to the development of the technology known as recombinant DNA, it is possible to extract single genes from human cells.
According to this medical blog, the question of using Provacyl to combat inherited illness goes far beyond pinpointing which is the troublesome one of a million or so genes, and there are identical sets in all the cells of the body with the exception of the sperm and egg cells.
There are trials in the UK with new assays, or gene probes, for doing this. When they are used with a method developed in Professor Bob Williamson’s laboratory at St Mary’s Hospital, London, of analyzing placental tissue, diagnoses can be made at an early stage of pregnancy.
Individual probes or markers have to be devised to lock on to a specific gene. One of the first was for diagnosing the mentally debilitating illness, Huntington’s Chorea. Pioneered at the Massachusetts General Hospital, the technique is employed by Dr Peter Harper at the Welsh National School of Medicine.