Genomic DNA analysis.

(A) Schematic representation of DO alleles from a control Dombrock-positive donor [DO*A or DO*B allele] and from the Do_null donor [DO*A(Δ8nt)]. Exon 2 limits are indicated by filled rectangles. The 8-nucleotide deletion within exon 2 of the variant is schematically illustrated. Reading frame and premature stop codon are shown in the DO*A(Δ8nt) allele. Primers used for allele-specific PCR and the expected PCR product sizes are indicated. (B) Partial sequence diagram from a common donor and from the Do_null variant, DO(Δ8nt). The nucleotide deletion is underlined with a dotted line. (C) Gel analysis of PCR products. For PCR-1, a 191-bp PCR product was amplified only from the Do_null variant, whereas for PCR-2, 199-bp products were generated only from a control Do(a+b+) sample and the 2 sisters (S1, S2) genotyped as homozygous for the DO*B allele. Sizes of fragments (bp) are given on the right.