Pyruvate Kinase Deficiency
Summary
Pyruvate kinase deficiency is the most common enzyme deficiency of the glycolytic pathway in red blood cells. Without adequate pyruvate kinase, red blood cells cannot produce enough ATP for survival, leading to their premature destruction (chronic haemolytic anaemia).
Practical takeaway
Carrier frequency is moderately high across European populations. Partner testing is available. The encouraging context: PK deficiency now has a targeted oral therapy. Realised does not calculate reproductive risk or advise on reproductive decisions.
Evidence detail
What Carrier Status Means For You
You are not affected. One working copy of PKLR produces sufficient pyruvate kinase. Carriers may have slightly reduced red blood cell PK activity on biochemical testing but have no clinical symptoms. Standard 25/50/25 recessive inheritance applies.
Population Context
PK deficiency occurs worldwide. R510Q is the most common variant in Europeans. Other variants are more common in Asian, Middle Eastern, and African populations. It is the most common inherited cause of non-spherocytic haemolytic anaemia.
Limitations
23andMe tests 1 of over 300 known PKLR variants. Coverage is minimal. Enzymatic testing (measuring PK activity) is often used diagnostically.