Submitted September 13, 2006
Accepted February 14, 2007
A complex splicing defect associated with homozygous ankyrin-deficient hereditary spherocytosis
E Jennifer Edelman, Yelena Maksimova, Feride Duru, Cigdem Altay, and Patrick G Gallagher*
Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
Ondokuz Mayys University, Samsun, Turkey
Hacettepe University, Ankara, Turkey
* Corresponding author; email: patrick.gallagher{at}yale.edu.
Defects in erythrocyte ankyrin are the most common cause of typical, dominant hereditary spherocytosis (HS). Detection of ankyrin gene mutations has been complicated by allelic heterogeneity, large gene size, frequent de novo mutations, and associated mRNA instability. Using denaturing high-performance liquid chromatography (DHPLC)-based mutation detection, a mutation in the splice acceptor of exon 17 was discovered in a Turkish family. Reticulocyte RNA and functional minigene splicing assays in heterologous cells revealed that this mutation was associated with a complex pattern of aberrant splicing, suggesting removal of intron 16 is important for ordered ankyrin mRNA splicing. As predicted by clinical, laboratory, and biochemical studies, the parents were heterozygous and the proband homozygous for this mutation. These data indicate that DHPLC offers a highly sensitive, economical, and rapid method for mutation detection and, unlike previously suggested, homozygosity for a mutation associated with dominant ankyrin-linked HS may be compatible with life.
