Instituto Valenciano de Microbiología

Masía El Romeral
Ctra. de Bétera a San Antonio Km. 0.3
46117 Bétera (Valencia)
Phone. 96 169 17 02
Fax 96 169 16 37
CIF B-96337217


Glucose-6-phosphate dehydrogenase deficiency, ..., (Glucose-6-phosphate dehydrogenase deficiency) - G6PD gene.

Glucose - 6-fosfatodeshidrogenasaes a genetic disease that occurs more frequently in males. This disorder primarily affects red blood cells. In affected individuals, a defect in an enzyme called glucose 6-phosphate causes erythrocytes are destroyed earlier than usual.

The most common medical problem associated with glucose-6-phosphate dehydrogenase deficiency is hemolytic anemia, which occurs when the erythrocytes are destroyed faster than the body can replace them . This type of anemia causes pallor, jaundice, dark urine, fatigue, shortness of breath and rapid heart rate. In people with the disorder, hemolytic anemia is often triggered by bacterial or viral infections or certain medications (such as some antibiotics and drugs used to treat malaria). Hemolytic anemia can also occur after the ingestion of beans or after inhalation of pollen plants (a reaction called favismo).

This process is due to mutations in the G6PD gene, located on chromosome X brazolargo of (Xq28). This gene encodes an enzyme called glucose-6-phosphate dehydrogenase. This enzyme is involved in normal processing of carbohydrates. It also protects the erythrocytes from the effects of potentially harmful molecules called reactive oxygen species, products of normal cellular functions.

They have identified more than 140 mutations in the G6PD gene in individuals with glucose-6-phosphate dehydrogenase deficiency. Most of these mutations change amino acids in the enzyme glucose-6-fosfato.Estos changes, alter the structure and normal function of the enzyme or reduce the amount of the enzyme in the cells. If mutations in the gene reduce the amount of glucose-6-phosphate dehydrogenase or alter its structure, this enzyme can no longer perform its protective role. Consequently, the reactive oxygen species can accumulate and damage the erythrocytes. Factors such as infections, certain medications, or ingestion of beans may increase concentrations of reactive oxygen species, which causes erythrocytes decompose faster than the body can replace them . A reduction in red cell concentrations results in the signs and symptoms of hemolytic anemia. It is believed that carriers of a mutation in G6PD gene may be partially protected against malaria. This is because a reduction in the amount of glucose-6-dehydrogenase functional makes it more difficult for the parasite to invade red blood cells.

This disease is inherited in a recessive X - linked pattern in males, an altered copy of the gene in each cell is sufficient to cause disease. In women, a mutation would have to happen in both copies of the gene alteration wing to give place. Because it is unlikely that women have two altered copies of this gene, males are affected by X - linked recessive disorders much more frequently than women. A feature of the X - linked inheritance is that fathers can not pass X - linked traits to their sons chromosome.  

Tests in IVAMI: in IVAMI perform detection of mutations associated with glucose-6-phosphate by the complete PCR amplification of exons G6PD gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).