Genetics, transplantation

Genetics, transplantation: The field of biology and medicine relating to the genes that govern the acceptance or rejection of a transplant.

The most important genes deciding the fate of a transplanted cell, tissue, or organ belong to what is termed the MHC (the major histocompatibility complex). The MHC was first identified through tumor transplantation studies in mice by Peter Gorer in 1937. In 1980 George Snell, Jean Dausset and Baruj Benacerraf received the Nobel prize in Physiology or Medicine for their contributions to the discovery and understanding of the MHC.

The MHC is the most highly polymorphic genetic system expressed in people. By “polymorphic” is meant that there are multiple forms of the gene (polymorphisms) occurring at a given gene locus. The chance for unrelated people to be MHC-identical is low.

The main function of the MHC antigens is peptide presentation to the immune system to help distinguish self from non-self. These antigens are called HLA (human leukocyte antigens). They consists of three regions: class I (HLA-A,B,Cw), class II (HLA-DR,DQ,DP) and class III (no HLA genes).

The need for HLA matching depends on the type of transplant. In bone marrow transplantation, HLA matching is an absolute necessity, lest the cells be rejected. In corneal transplantation, HLA matching is less relevant because of the lack of blood vessels in the cornea and the “immunological privilege” of the cornea. HLA matching is not crucial but is beneficial to the success of most solid organ transplantation including kidney, liver, heart, lung, pancreas, and intestine.

Read Also:

  • Genital herpes

    Genital herpes: An infection by human herpes virus that is transmitted through intimate contact with the moist mucous linings of the genitals. This contact can involve the mouth, the vagina, or the genital skin. Following infection, the virus travels to nerve roots near the spinal cord and settles there permanently. When an infected person has […]

  • Genital

    Genital: Pertaining to the external and/or internal organs of reproduction.

  • Genital wart

    Genital wart: A wart in the moist skin of the genitals or around the anus. Genital warts are due to a human papillomavirus (HPV). The HPVs, including those that cause genital warts, are transmitted through sexual contact. HPV can also be transmitted from mother to baby during childbirth. Most people infected with HPV have no […]

  • Genitalia

    Genitalia: The male or female reproductive organs. The genitalia include internal and external structures. The female internal genitalia are the ovaries, Fallopian tubes, uterus, cervix, and vagina. The female external genitalia are the labia minora and majora (the vulva) and the clitoris. The male internal genitalia are the testes, epididymis, and vas deferens. The male […]

  • Genome

    Genome: All the genetic information possessed by any organism (for example, the human genome, the elephant genome, the mouse genome, the yeast genome, and the genome of a bacterium). Humans and many other higher animals actually have two genomes’a chromosomal genome and a mitochondrial genome’that together make up their genome.

Disclaimer: Genetics, transplantation definition / meaning should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. All content on this website is for informational purposes only.