The health effects caused by sickle cell disease can be mild or severe depending on which form a person experiences. As an inheritable condition, abnormal genes are the cause of sickle cell symptoms like pain and anaemia, and the type of abnormal gene a parent passes on can dictate the effects of the disorder.
With haemoglobin beta thalassemia (HbS) sickle cell disease, those affected receive abnormal genes from both parents, but the effects of this disorder are not usually severe.
As an inherited condition, people with sickle cell disease receive certain mutated genes from their parents:
When it comes to HbS sickle cell disease, people receive one haemoglobin S gene from one parent and one beta thalassemia gene from the other. Additionally, there are two distinct subtypes of beta thalassemia genes:
Some people develop a highly rare form of sickle cell disease by inheriting one haemoglobin S gene and one irregular gene (such as haemoglobin D, E, and O genes).