Mutation in sph^J.

(A) Top, schematic representation of the Spna1 cDNA with numbers above the line corresponding to the repeats of 106 aa that comprise the α-spectrin protein. Shown below the cDNA schematic are nucleotide (top) and amino acid (bottom) sequence of the +/+ andsph^J/sph^J cDNAs. (B) Genomic PCR of tail DNA from +/+ and sph^J/+ mice. Lane M is marker; sizes in kb are shown on left. Lanes labeled 50: PCR products from a reaction containing primers (47 and 50) that amplify wild-type and mutant alleles of Spna1. Lanes labeled 50 and 49: PCR products from a reaction containing primers (47 and 49) designed to identify the C→A transition in thesph^J allele. Genotypes of mice are noted above each bracketed pair of reactions.