The term hereditary spherocytosis (HS) covers a range of genetically and phenotypically variable red blood cell (RBC) cytoskeleton disorders, caused by defects in proteins that link the membrane skeleton to the lipid bilayer. Nonsense and frameshift mutations of ankyrin, band 3 and β-spectrin are often responsible for dominant HS, while homozygosity or compound heterozygosity of defects in ankyrin, α-spectrin, or protein 4.2 cause recessive HS (Eber & Lux, 2004; Iolascon & Avvisati, 2008). Protein 4.2 is an important component of the RBC cytoskeleton, representing approximately 5% of the membrane protein content (Satchwell et al, 2009). It binds the N-terminal cytoplasmic domain of band 3 and regulat... More
The term hereditary spherocytosis (HS) covers a range of genetically and phenotypically variable red blood cell (RBC) cytoskeleton disorders, caused by defects in proteins that link the membrane skeleton to the lipid bilayer. Nonsense and frameshift mutations of ankyrin, band 3 and β-spectrin are often responsible for dominant HS, while homozygosity or compound heterozygosity of defects in ankyrin, α-spectrin, or protein 4.2 cause recessive HS (Eber & Lux, 2004; Iolascon & Avvisati, 2008). Protein 4.2 is an important component of the RBC cytoskeleton, representing approximately 5% of the membrane protein content (Satchwell et al, 2009). It binds the N-terminal cytoplasmic domain of band 3 and regulates the avidity of the interaction between band 3 and ankyrin within the band 3 macrocomplex (Bruce et al, 2003). Protein 4.2 is encoded by the EPB42 gene, which encompasses approximately 20 kb, containing 13 exons and 12 introns, and maps to 15q15-q21 (Korsgren & Cohen, 1991).
