Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive

X-linked recessive

X-linked recessive inheritance is a mode of inheritance in which a mutation in a gene on the X chromosome causes the phenotype to be expressed in males and in females who are homozygous for the gene mutation X-linked recessive inheritance is a mode of inheritance in which a mutation in a gene on...

 hereditary disease characterised by abnormally low levels of glucose-6-phosphate dehydrogenase

Glucose-6-phosphate dehydrogenase

Glucose-6-phosphate dehydrogenase is a cytosolic enzyme in the pentose phosphate pathway , a metabolic pathway that supplies reducing energy to cells by maintaining the level of the co-enzyme nicotinamide adenine dinucleotide phosphate...

 (abbreviated G6PD or G6PDH), a metabolic enzyme involved in the pentose phosphate pathway

Pentose phosphate pathway

The pentose phosphate pathway is a process that generates NADPH and pentoses . There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars...

, especially important in red blood cell

Red blood cell

Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...

 metabolism. G6PD deficiency is the most common human enzyme defect. Individuals with the disease may exhibit nonimmune hemolytic anemia

Hemolytic anemia

Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells , either in the blood vessels or elsewhere in the human body . It has numerous possible causes, ranging from relatively harmless to life-threatening...

 in response to a number of causes, most commonly infection

Infection

An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...

 or exposure to certain medications or chemicals.