Sickle Cell Anemia

Educating on sickle cell risk

Members of the public in sub-Saharan Africa who are carriers of the hereditary disease sickle cell disease must be educated aggressively through public health campaigns to raise awareness of the risks of parenting offspring ...

Nov 24, 2014
popularity not rated yet | comments 0

Discovery could lead to new cancer treatment

A team of scientists from the University of Colorado School of Medicine has reported the breakthrough discovery of a process to expand production of stem cells used to treat cancer patients. These findings could have implications ...

Aug 29, 2014
popularity 4.4 / 5 (5) | comments 0

How the immune system fights off malaria

The parasites that cause malaria are exquisitely adapted to the various hosts they infect—so studying the disease in mice doesn't necessarily reveal information that could lead to drugs effective against ...

Jan 13, 2014
popularity 4 / 5 (2) | comments 0 | with audio podcast

Sickle-cell disease (SCD), or sickle-cell anaemia (or anemia, SCA) or drepanocytosis, is an autosomal recessive genetic blood disorder with overdominance, characterized by red blood cells that assume an abnormal, rigid, sickle shape. Sickling decreases the cells' flexibility and results in a risk of various complications. The sickling occurs because of a mutation in the hemoglobin gene. Life expectancy is shortened. In 1994, in the US, the average life expectancy of persons with this condition was estimated to be 42 years in males and 48 years in females, but today, thanks to better management of the disease, patients can live into their 50s or beyond. In the UK, the current life expectancy is estimated to be 53–60 years of age.

Sickle-cell disease, usually presenting in childhood, occurs more commonly in people (or their descendants) from parts of tropical and sub-tropical regions where malaria is or was common. One-third of all indigenous inhabitants of Sub-Saharan Africa carry the gene, because in areas where malaria is common, there is a fitness benefit in carrying only a single sickle-cell gene (sickle cell trait). Those with only one of the two alleles of the sickle-cell disease, while not totally resistant, are more tolerant to the infection and thus show less severe symptoms when infected.

The prevalence of the disease in the United States is approximately 1 in 5,000, mostly affecting Americans of Sub-Saharan African descent, according to the National Institutes of Health. In the United States, about 1 out of 500 African-American children born will have sickle-cell anaemia.

Sickle-cell anaemia is the name of a specific form of sickle-cell disease in which there is homozygosity for the mutation that causes HbS. Sickle-cell anaemia is also referred to as "HbSS", "SS disease", "haemoglobin S" or permutations thereof. In heterozygous people, who have only one sickle gene and one normal adult haemoglobin gene, it is referred to as "HbAS" or "sickle cell trait". Other, rarer forms of sickle-cell disease include sickle-haemoglobin C disease (HbSC), sickle beta-plus-thalassaemia (HbS/β+) and sickle beta-zero-thalassaemia (HbS/β0). These other forms of sickle-cell disease are compound heterozygous states in which the person has only one copy of the mutation that causes HbS and one copy of another abnormal haemoglobin allele.

The term disease is applied, because the inherited abnormality causes a pathological condition that can lead to death and severe complications. Not all inherited variants of haemoglobin are detrimental, a concept known as genetic polymorphism.

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

Vaccines may make war on cancer personal

In the near future, physicians may treat some cancer patients with personalized vaccines that spur their immune systems to attack malignant tumors. New research led by scientists at Washington University ...

Elderly brains learn, but maybe too much

A new study led by Brown University reports that older learners retained the mental flexibility needed to learn a visual perception task but were not as good as younger people at filtering out irrelevant ...