title: Simultaneous screening for three mutations in the ABCB1 gene.
abstract: A noncoding C3435T mutation in exon 26 of the ABCB1 gene was found to be often associated with a G2677T(A) mutation in exon 21 encoding an Ala893Ser P-glycoprotein and with a noncoding C1236T mutation in exon 12. We developed a Pyrosequencing screening method that simultaneously detects all three mutations. After separate PCRs for each exon, the sequences around the potentially mutated nucleotide positions were simultaneously analyzed in a multiplex assay. The method was tested with DNA from 100 volunteers. Allele frequencies of the T1236, T2677, and T3435 alleles were 44, 42, and 50%, respectively. A mutation at position 3435 occurred together with a mutation at position 2677 or 1236 in 64 and 65% of the subjects, respectively. The most frequent haplotype, with 44.4%, was not mutated at all three positions, i.e., C1236, G2677, C3435. The second most frequent haplotype, with 37.1%, was mutated at all three positions, i.e., T1236, T2677, T3435. The most frequent genotype, with 36%, was heterozygously mutated at all three positions, i.e., C/T1236, G/T2677, C/T3435. The next most frequent genotypes were a homozygous nonmutated genotype, with 20%, and a homozygous mutated genotype, with 13%.
authors.affiliation: Pharmazentrum Frankfurt, Institute of Clinical Pharmacology, Johann Wolfgang Goethe University, Theodor Stern Kai 7, D-60590 Frankfurt, Germany. j.loetsch@em.uni-frankfurt.de
authors.forename: Jörn
authors.initials: J
authors.lastname: Lötsch
authors.forename: Carsten
authors.initials: C
authors.lastname: Skarke
authors.forename: Gerd
authors.initials: G
authors.lastname: Geisslinger
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics; D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D004247:DNA / Q000097:blood; D004252:DNA Mutational Analysis / Q000379:methods*; D005091:Exons; D005787:Gene Frequency; D006239:Haplotypes; D006801:Humans; D009154:Mutation; D020641:Polymorphism, Single Nucleotide
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D018528:ATP-Binding Cassette Transporters; D004247:DNA