What is the G6PD gene?
The G6PD gene codes for the glucose-6-phosphate dehydrogenase enzyme. The G6PD enzyme is part of the pentose phosphate pathway and supplies the energy needed to produce NADPH. NADPH then is responsible for maintaining the supply of glutathione, an antioxidant. Red blood cells are the only type of cells that rely entirely on this pathway and thus G6PD deficiency can cause the destruction of red blood cells through a build-up of oxidants.
While many people have no symptoms from this disorder, Genetics Home Reference list the following as possible effects: “The most common medical problem associated with glucose-6-phosphate dehydrogenase deficiency is hemolytic anemia, which occurs when red blood cells are destroyed faster than the body can replace them. This type of anemia leads to paleness, yellowing of the skin and whites of the eyes (jaundice), dark urine, fatigue, shortness of breath, and a rapid heart rate.” Read more here.
This gene is located on the X chromosome, so males only have one copy of the gene and thus are more likely to be affected by G6PD deficiency than females.
G6PD deficiency is also known as Favism due to the negative effect of fava (or broad) beans. It often can be triggered by bacterial or viral infections as well. Additionally, there are several medications that also cause problems for those with G6PD deficiency including quinones, methylene blue, and certain antibiotics.
Genetic variants that can cause G6PD deficiency:
The variants below are mainly found in the older 23andMe data. The current version (from August 2017 – present) doesn’t include most of this information.
Most of the variants below are listed in ClinVar, a database of genetic variants of clinical importance. This list covers some of the variants available in 23andMe raw data. There are other genetic mutations linked to G6PD deficiency that are not covered in 23andMe or AncestryDNA data, so if you have symptoms, don’t rely on this in-leu of a doctor-ordered medical lab test.
|G6PD variant||Risk Allele|
Diet and Supplements that may help:
This is one disorder that you really should talk with your doctor about and possibly consult a dietician. In addition to Fava beans and other legumes, there are quite a few foods that should be avoided. As far as medications to be avoided, again, talk with your doctor or pharmacist.
One study (and several anecdotal reports) suggest that N-acetylcysteine may be a good supplement for G6PD deficiency. Again, do some more research and talk with a doc on this.
More to read: