The vast science of DNA and donor matching
I am just about to realize all the varieties of life which can be seen with today’s technology. It is indisputably so spectacular and magical. (Especially when it comes to microscopic life, which is a diverse field of science in which humans still are learning from).
It is always a privilege to be a part of humanitarian work, and it gets even more exciting when every day is about saving peoples lives. Nevertheless, I find myself searching for mutations in the human genome every day. Human leukocyte antigen system is my “field of interest” – the so called vast science of major histocompatibility complex in humans.
HLA have other roles. They are sometimes involved in mate selection. They may protect against or allow cancer. They may mediate autoimmune disease (examples: juvenile diabetes, coeliac disease).
Aside from the genes encoding the 6 major antigens, there are a large number of other genes, many involved in immune function located on the HLA complex. Diversity of HLA in human population is one aspect of disease defense, and, as a result, the chance of two unrelated individuals having identical HLA molecules on all loci is very low. Historically, HLA genes were identified as a result of the ability to successfully transplant organs between HLA similar individuals.
So what makes this job hard? Well, let’s face it. The transcription (or let us call it “data”) is extremely fuzzy. Now check this out:
HLA are extremely variable loci
MHC loci are some of the most genetically variable coding loci in mammals, and the human HLA loci are no exceptions. Despite the fact that the human population went through a constriction more than 150 000 years ago that was capable of fixing many loci, the HLA loci appear to have survived such a constriction with a great deal of variation.
Now that’s the problem. There are so many variations. This is not about remembering those mathematical and physical equations from school.
In 1968, it was discovered that matching these antigens between kidney donor and recipient improved the likelihood of kidney survival in the recipient.