Editing Pyruvate kinase (section)

=== Deficiency ===
Genetic defects of this enzyme cause the disease known as [[pyruvate kinase deficiency]]. In this condition, a lack of pyruvate kinase slows down the process of glycolysis. This effect is especially devastating in cells that lack [[mitochondria]], because these cells must use [[anaerobic glycolysis]] as their sole source of energy because the [[TCA cycle]] is not available. For example, [[red blood cells]], which in a state of pyruvate kinase deficiency, rapidly become deficient in ATP and can undergo [[hemolysis]]. Therefore, pyruvate kinase deficiency can cause chronic nonspherocytic [[hemolytic anemia]] (CNSHA).<ref>{{cite journal | vauthors = Grace RF, Zanella A, Neufeld EJ, Morton DH, Eber S, Yaish H, Glader B | title = Erythrocyte pyruvate kinase deficiency: 2015 status report | journal = American Journal of Hematology | volume = 90 | issue = 9 | pages = 825–30 | date = September 2015 | pmid = 26087744 | doi = 10.1002/ajh.24088 | pmc = 5053227 }}</ref>

==== PK-LR gene mutation ====
Pyruvate kinase deficiency is caused by an autosomal recessive trait. Mammals have two pyruvate kinase genes, PK-LR (which encodes for pyruvate kinase isozymes L and R) and PK-M (which encodes for pyruvate kinase isozyme M1), but only PKLR encodes for the red blood isozyme which effects pyruvate kinase deficiency. Over 250 PK-LR gene mutations have been identified and associated with pyruvate kinase deficiency. DNA testing has guided the discovery of the location of PKLR on chromosome 1 and the development of direct gene sequencing tests to molecularly diagnose pyruvate kinase deficiency.<ref>{{cite journal | vauthors = Climent F, Roset F, Repiso A, Pérez de la Ossa P | title = Red cell glycolytic enzyme disorders caused by mutations: an update | journal = Cardiovascular & Hematological Disorders Drug Targets | volume = 9 | issue = 2 | pages = 95–106 | date = June 2009 | pmid = 19519368 | doi = 10.2174/187152909788488636 }}</ref>