What should you know about G6PD deficiency inheritance?

The G6PD gene is located on the X chromosome. Because people inherit different combinations of sex chromosomes, the pattern can affect relatives in different ways. Some people have low enzyme activity and develop episodes of red-cell breakdown after particular medicines, infections, or foods; others have milder activity changes or no obvious symptoms. A person may carry or pass on a gene change without having the same experience as another family member. This is why family history alone cannot confirm an individual's status.

Tell your doctor if a relative has confirmed G6PD deficiency or has experienced jaundice, pale skin, or dark urine after an illness or medicine. A blood test can help assess enzyme activity. Keep the result with your medical records and ask a pharmacist to check new medicines. Genetic counselling may help a family understand testing options, pregnancy questions, and what results could mean for children or siblings.

Seek urgent medical attention for yellow skin or eyes, dark urine, sudden pallor, severe tiredness, breathlessness, fast heartbeat, or fainting after an infection or new medicine. These symptoms can signal rapid red-cell breakdown and should not wait for routine family testing.

Ask how the family pattern may affect you or your children, whether testing should be arranged before a medicine or pregnancy, and how to record the result. Ask which symptoms need urgent help and whether a relative should receive genetic counselling.