Sequencings

Markers / G6PD

rs1050828

G6PD deficiency, the A- variant

GeneG6PD
PositionchrX:153,764,217
VersionsC / T
Evidenceestablished

What this position does

G6PD deficiency is the most common enzyme deficiency in the world. It is usually silent until something triggers it: certain antimalarials, some antibiotics, the gout drug rasburicase, and fava beans can all cause red blood cells to break down. The gene is on the X chromosome, so men have only one copy.

What each result means

If you carryWhat it means
No copies of the effect version
CC
You do not carry the A- variant
The A- variant is absent.
One copy
CT
One copy, which means different things by sex
In women, one copy usually means partial deficiency with a variable effect. In men there is only one copy, so this means deficiency.
Two copies
TT
Two copies, or hemizygous
Consistent with G6PD deficiency. This is genuinely worth telling a doctor and a pharmacist, because it changes which drugs are safe for you. It is confirmed with a simple enzyme blood test.

Worth knowing. This reads the A- variant, which is the common African form. Mediterranean and Asian forms are caused by different changes that are not read here, so a clear result does not rule out deficiency. The enzyme blood test does.

How common each version is

How many people carry each result

How to find out which you have

If you have taken a test with 23andMe, AncestryDNA, MyHeritage, Family Tree DNA, TellMeGen or Living DNA, this position is very likely already in the raw data file they gave you. You do not need another test.

One thing to watch if you look it up by hand: testing companies report some positions from one DNA strand and some from the other, and the file does not say which. Read the letters as they appear and you will get the opposite of the truth for some positions. Sequencings resolves that automatically.

Source

CPIC Guideline for Rasburicase and G6PD

Coordinates and allele pair verified against Ensembl GRCh37. Direction of effect verified against VEP protein consequences or 1000 Genomes population frequency. Category: Medicine response.

Where this fits

Common questions

What is rs1050828?

rs1050828 is a position in the G6PD gene on chromosome X. G6PD deficiency is the most common enzyme deficiency in the world. It is usually silent until something triggers it: certain antimalarials, some antibiotics, the gout drug rasburicase, and fava beans can all cause red blood cells to break down. The gene is on the X chromosome, so men have only one copy.

What does it mean if I have TT at rs1050828?

Two copies, or hemizygous. Consistent with G6PD deficiency. This is genuinely worth telling a doctor and a pharmacist, because it changes which drugs are safe for you. It is confirmed with a simple enzyme blood test.

What does it mean if I have CC at rs1050828?

You do not carry the A- variant. The A- variant is absent.

How do I find out my rs1050828 genotype?

If you have taken a home DNA test, this position is very likely in the raw data file you were given. Sequencings reads that file in your browser without uploading it, and resolves which DNA strand each position was reported from, which is the step most manual lookups get wrong.

This is reference information, not medical advice, and not a diagnosis. See the medical disclaimer. Category: Medicine response.