hla system

The human leukocyte antigen (HLA) system is the locus of genes that encode for proteins on the surface of cells that are responsible for regulation of the immune system in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and has many other functions.

The HLA genes are the human versions of the major histocompatibility complex (MHC) genes that are found in most vertebrates (and thus are the most studied of the MHC genes). The proteins encoded by certain genes are also known as antigens, as a result of their historic discovery as factors in organ transplants. The major HLAs are essential elements for immune function. Different classes have different functions:

  • HLAs corresponding to MHC class I (A, B, and C) present peptides from inside the cell. For example, if the cell is infected by a virus, the HLA system brings fragments of the virus to the surface of the cell so that the cell can be destroyed by the immune system. These peptides are produced from digested proteins that are broken down in the proteasomes. In general, these particular peptides are small polymers, about 9 amino acids in length.[citation needed] Foreign antigens presented by MHC class I attract killer T-cells (also called CD8 positive- or cytotoxic T-cells) that destroy cells.
  • HLAs corresponding to MHC class II (DP, DM, DOA, DOB, DQ, and DR) present antigens from outside of the cell to T-lymphocytes. These particular antigens stimulate the multiplication of T-helper cells, which in turn stimulate antibody-producing B-cells to produce antibodies to that specific antigen. Self-antigens are suppressed by regulatory T cells.
  • HLAs corresponding to MHC class III encode components of the complement system.

HLAs have other roles. They are important in disease defense. They are the major cause of organ transplant rejections. They may protect against or fail to protect (if down-regulated by an infection) against cancers. Mutations in HLA may be linked to autoimmune disease (examples: type I diabetes, coeliac disease). HLA may also be related to people’s perception of the odor of other people, and may be involved in mate selection, as at least one study found a lower-than-expected rate of HLA similarity between spouses in an isolated community.

Aside from the genes encoding the 6 major antigen-presenting proteins, there are a large number of other genes, many involved in immune function, located on the HLA complex. Diversity of HLAs in the human population is one aspect of disease defense, and, as a result, the chance of two unrelated individuals with identical HLA molecules on all loci is very low. HLA genes have historically been identified as a result of the ability to successfully transplant organs between HLA-similar individuals.

anonymous asked:

If the DNA matched that's means that sarada could have her dna because karin implanted her cells in sarada when she was born. Suigetsu just make the test with karin's material not sasuke's material. But sarada has sakura and sasuke DNA too of course. But it strange that karin still has her umbilical cord. Why do you think karin didn't want suigetsu to touch her stuff? And he said he was not sure that the cord was from karin.

Okay, first of all, I am still hungover from a friend’s Birthday Breakfast this morning no more day drinking ever

so there is a very high possibility my informations I am giving here are not 100% correct, my last biology class was 80 years ago, I will not go into deeper, complex biology, I am not a major in biology or medicine and my logic is wishy washy. Second, I am not sure how strict Kishimoto is following the laws of heredity and blood compability so please don’t take this too serious.

I will go with your theory, that Sarada is Sasuke’s and Sakura’s biological child but got Karin’s cells transplanted, that’s why the test said the DNAs matched, is that right? First, according to Naruto Wikia, the bloodtypes of Sakura is 0 and Sasuke is AB. Meaning Sarada is a bloodtype A or B. Bloodtypes A or B can only receive whole blood or red blood cell donations from A (for A), B (for B) or 0 (for both), but it is possible to receive a bloodplasma donation from an AB though, but I will get to this later. This means bloodtype A or B can also only receive an organ transplant from A or B and 0. According to Naruto Wikia, Karin has the bloodtype AB, which makes it impossible for her to be a whole blood donor or a compatible organ donor.

But let’s just pretend it is possible for Karin to implant one of her organs or her blood into Sarada. In the case of the organ transplant, Sarada’s original DNA would not change. She only would have 2 different DNAs in her body, but Karin’s DNA would only be found in the tissue or organ she planted into Sarada. Since Suigetsu took a sample from Sarada’s oral mucosa, I guess we can cross out the organ/tissue donation theory. Same goes for the blood transfer fantasy. If Sarada received a erythrocyte transfusion from Karin, it wouldn’t affect the DNA test at all because red blood cells don’t have a nucleus, meaning there is no DNA in them. If Sarada received a bloodplasma or whole blood transfusion then there is a chance of temporarily having a different DNA, but billions of new blood cells are produced and renewed daily, meaning this is only a temporary state and since the Manga does not indicate Karin ever meeting Sarada recently, we can x-out this theory too.

If you are being extra fancy and thinking of a stem cell therapy (let’s pretend that Sarada and Karin have a compatible HLA-system) , then there is a high possibility that Sarada has Karin’s DNA in her blood. Even though it is very unlikely that Karin went through the effort of transfering her stem cells into Sarada, let’s just go there for the hell of it. Since the bone marrow is responsible for the production of blood cells, after a stem cell therapy Sarada most likely posesses Karin’s blood, meaning a DNA match can be found through a blood test. BUT, again, Suigetsu took a swab from Sarada’s oral mucosa which has nothing to do with the bloodcell production, thus containing Sarada’s original DNA from Sasuke and Sakura.

So, even according to your theory with the cell transplant, there is no way the test would show a “Match” if Suigetsu really took Karin’s material for the DNA test and Sarada is SS’s biologial kid (which canonly she is). I hope this wasn’t too confusing (and boring) and my explanations and memory is kinda correct.