Scanning electron micrograph showing sickle cells in the midst of normal RBC’s
Sickle cell anaemia is a condition in which the red blood cells assume an abnormal rigid sickle shape
There is decrease in flexibility of the red cells, which impair their ability to flow freely through blood capillaries
It can result in conditions like vaso occlusive crisis, splenic sequestration crisis, aplastic crisis, haemolytic crisis
It is an autosomal recessive condition
Sickle cell anaemia – Mnemonic
Sickle cell anaemia occurs due to the replacement of hydrophilic amino acid glutamic acid with hydrophobic amino acid valine at the 6th position of the beta globin chain of haemoglobin
The inclusion of the hydrophobic ( non polar ) amino acid promotes non covalent polymerisation of haemoglobin resulting in distortion of the RBC’s into a sickle shape
So, how to remember the amino acids involved?
Just remember this memory key – The Villain replaced the Good guy
The Villain is Valine
The Good guy is Glutamic acid
So you will in turn remember that Valine replaces Glutamic acid