Editing Polymerase chain reaction (section)

===Medical and diagnostic applications===
Prospective parents can be tested for being [[genetic carrier]]s, or their children might be tested for actually being affected by a [[cystic fibrosis|disease]].<ref name="Saiki1"/> DNA samples for [[Prenatal diagnosis|prenatal testing]] can be obtained by [[amniocentesis]], [[chorionic villus sampling]], or even by the analysis of rare fetal cells circulating in the mother's bloodstream. PCR analysis is also essential to [[preimplantation genetic diagnosis]], where individual cells of a developing embryo are tested for mutations.
* PCR can also be used as part of a sensitive test for ''[[tissue typing]]'', vital to [[organ transplantation]]. {{As of|2008|post=,}} there is even a proposal to replace the traditional antibody-based tests for [[blood type]] with PCR-based tests.<ref>{{cite journal | vauthors = Quill E | title = Medicine. Blood-matching goes genetic | journal = Science | volume = 319 | issue = 5869 | pages = 1478–79 | date = March 2008 | pmid = 18339916 | doi = 10.1126/science.319.5869.1478 | s2cid = 36945291 }}</ref>
* Many forms of cancer involve alterations to ''[[oncogene]]s''.  By using PCR-based tests to study these mutations, therapy regimens can sometimes be individually customized to a patient. PCR permits early diagnosis of [[malignant]] diseases such as [[leukemia]] and [[lymphoma]]s, which is currently the highest-developed in cancer research and is already being used routinely. PCR assays can be performed directly on genomic DNA samples to detect translocation-specific malignant cells at a sensitivity that is at least 10,000 fold higher than that of other methods.<ref>{{cite book|last1=Tomar|first1=Rukam|title=Molecular Markers and Plant Biotechnology|date=2010|publisher= New India Publishing Agency|location= Pitman Pura, New Delhi|isbn= 978-93-80235-25-7|page=188}}</ref> PCR is very useful in the medical field since it allows for the isolation and amplification of tumor suppressors. Quantitative PCR for example, can be used to quantify and analyze single cells, as well as recognize DNA, mRNA and protein confirmations and combinations.<ref name="Garibyan, Avashia 1–4"/>