Sickle Cell Anemia 1) Single nucleotide substitution (“point mutation”) in the gene for the beta chain of hemoglobin. 2) Different amino acid gets placed in the peptide chain. 3) Different amino acid gets placed in the peptide chain.. 4) Beta chain synthesized from the sickle-cell allele does not “fold” correctly and hempglobin molecules “clump” together forming a red blood cell that resembles a sickle. 5) Sickled cells die early (10-20 days vs. 120 days) producing anemia. 6) Sickled cells clog the fine capillaries, leading to lack of oxygen in target organs.

http://bio.winona.msus.edu/berg/308s04/Lec-note/19-new.htm

Rapid breakdown of sickled cells Hemoglobin molecules “clump” Sickle-shape red blood cells Skeletal problems Impeded circulation Organ damage Pain Infection risk Overactive bone marrow Fatigue Impaired development Anemia

http://www. ncbi. nlm. nih. gov/books/bv. fcgi. call= bv. View http://www.ncbi.nlm.nih.gov/books/bv.fcgi?call= bv.View..ShowSection&rid=gnd.section.98

http://peptide. ncsa. uiuc http://peptide.ncsa.uiuc.edu/tutorials_current/Sickle_Cell_Anemia/SC2001/intro.html

http://www. blackwellpublishing. com/ridley/images/sickle_cell_anaemia http://www.blackwellpublishing.com/ridley/images/sickle_cell_anaemia.jpg

Why is SCA so common in some areas? http://anthro.palomar.edu/synthetic/synth_7.htm

http://anthro.palomar.edu/synthetic/synth_7.htm