Page 454 - First Aid for the USMLE Step 1 2020, Thirtieth edition [MedicalBooksVN.com]_Neat

410 SectIon III Hematology and oncology ` hematology and oncology—PhySIology Hematology and oncology ` hematology and oncology—PhySIology

` hematology and oncology—PhySIology

Hemoglobin electrophoresis

Origin On a gel, hemoglobin migrates from the
negatively charged cathode to the positively
AA ↑ Normal adult
charged anode. HbA migrates the farthest,
AF ↑ Normal newborn followed by HbF, HbS, and HbC. This is
AS ↑ Sickle cell trait because the missense mutations in HbS and
HbC replace glutamic acid ⊝ with valine
SS ↑ Sickle cell disease
(neutral) and lysine ⊕, respectively, making
AC ↑ Hb C trait HbC and HbS more positively charged than
CC ↑ Hb C disease HbA.
SC ↑ Hb SC disease
C S F A
Cathode A: normal hemoglobin β chain (HbA, adult) Anode
F: normal hemoglobin γ chain (HbF, fetal)
S: sickle cell hemoglobin β chain (HbS)
C: hemoglobin C β chain (HbC) A Fat Santa Claus can’t (cathode Ž anode) go
far.

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