Final answer:
It is true that HbSC patients usually have milder disease severity compared to HbSS patients, due to the presence of both sickle hemoglobin and hemoglobin C in HbSC individuals, allowing for better overall red blood cell function.
Step-by-step explanation:
It is true that patients with HbSC (one mutant hemoglobin S gene and one mutant hemoglobin C gene) typically have a milder disease severity than patients with HbSS, who possess two sickle cell genes. HbSC individuals produce both sickle hemoglobin (hemoglobin S) and hemoglobin C, resulting in a less severe form of sickle cell disease compared to HbSS individuals, who produce only hemoglobin S. This is due to the fact that while HbSC red blood cells can become sickle-shaped under certain conditions, there is typically enough normal hemoglobin function to maintain better red blood cell integrity and therefore decrease the frequency and severity of sickling episodes.
Sickle cell anemia is an autosomal recessive disorder caused by a single amino acid mutation in the beta-globin chain of hemoglobin. This condition is characterized by the production of abnormal hemoglobin S, which leads to the sickling of red blood cells, disrupting blood flow and oxygen delivery, causing the symptoms associated with anemia. Sickle cell trait carriers (who are heterozygous for the allele) typically experience fewer complications than those who are homozygous for the allele (HbSS).
In regions where malaria is prevalent, carrying one copy of the sickle cell gene provides a selective advantage, offering some protection against malaria. However, individuals who are homozygous for the sickle cell mutation (HbSS) do not experience this benefit and are likely to suffer from severe sickle cell disease.