How do we contract Sickle Cell Disease?

The normal hemoglobin is called “A” and the abnormal one “S”. Two people “AS” have a 1 in 4 risk with each pregnancy to give birth to a sick child “SS.

Each one of us is the result of our parent’s genetic inheritance one being the one which codes the hemoglobin. There are three different situations:

  • AA – Child inherits 2 normal genes (Father + Mother) no risk of SCD.
  • AS – Child inherits of 1 normal gene and 1 abnormal: parent can transmit the disease without knowing it. This is why is it essential to receive a screening test called “hemoglobin electrophresis”. If both parents are AS, the risk of having a sick child is of 1 in 4 for each birth.
  • SS – Child inherits of 2 abnormal genes. The most severe case of SCD.


La transmission de la drépanocytose