Simultaneous (AC)n microsatellite polymorphism analysis and single-stranded conformation polymorphism screening is an efficient strategy for detecting ankyrin-1 mutations in dominant hereditary spherocytosis.
Nonsense/stop mutations in the ankyrin-1 gene (ANK1) are a major cause of dominant HS (dHS) (frequency of 23% in German dHS patients). To date, no common mutation has been found and therefore a simple mutation screening is not feasible. The reduced expression of one cDNA allele in the (AC)n microsatellite polymorphism of the ankyrin-1 gene, as seen in about 20% of Czech patients with dHS, may identify candidates with a possible frameshift/nonsense mutation. In order to verify the efficiency of this screening we screened the ankyrin-1 gene of 22 Czech dHS patients for both the reduced cDNA allele expression in the frequent (AC)n and the common exonic 26/39 polymorphisms, as well as for polymerase chain reaction (PCR) single-stranded conformation polymorphisms in any one of the 42 exons of ANK1. Anomalous PCR products were sequenced. We found seven new ANK1 frameshift/nonsense mutations in nine patients with, but in none of six patients without, a reduced cDNA allele expression (efficiency of 78%). We conclude that screening of dHS patients for such a reduced allele expression in common ANK1 polymorphisms is an efficient procedure for the identification of candidates for frameshift/nonsense mutations in the ankyrin-1 gene.
Ozcan
Refik
R
Universitäts-Kinderklinik, Goettingen, Germany.
Jarolim
Petr
P
Lux
Samuel E
SE
Ungewickell
Ernst
E
Eber
Stefan W
SW
D017487:Ankyrins / Q000235:genetics*; D018389:Codon, Nonsense; D004252:DNA Mutational Analysis / Q000379:methods; D018076:DNA, Complementary / Q000235:genetics; D004910:Erythrocyte Membrane / Q000378:metabolism; D005260:Female; D016368:Frameshift Mutation; D015870:Gene Expression; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D018807:Polymorphism, Single-Stranded Conformational; D012333:RNA, Messenger / Q000235:genetics; D013103:Spherocytosis, Hereditary / Q000097:blood / Q000235:genetics*
C110202:ANK1 protein, human; D017487:Ankyrins; D018389:Codon, Nonsense; D018076:DNA, Complementary; D012333:RNA, Messenger