Fig. 1.

Comparative analysis of nucleotide and deduced amino acid sequences of Dahl S and Dahl R AngII/AVP receptor cDNAs. (a) Sequencing gels of Dahl S and Dahl R cDNAs spanning the A³⁵⁶ → G³⁵⁶ (Dahl R → Dahl S) nucleotide transition that results in a N119 substitution in Dahl S AngII/AVP receptor for S119 and T⁴⁸⁷ → C⁴⁸⁷ (Dahl R → Dahl S) nucleotide transition that results in a C163 substitution in Dahl S AngII/AVP receptor for R163. Nucleotide and amino acid numbering as per Ruiz-Opazo et al (4). Specific nucleotides (C, T, A, G) and 5′ to 3′ directions are indicated. (b) Schematic structure of the AngII/AVP receptor in the region around transmembrane domains H2 and H3. Open circles indicate amino acids common to both Dahl S and Dahl R AngII/AVP receptors. Black circles highlight the amino acids involved in the substitutions. (c) Detection of the N119S and C163R mutations in genomic DNA by using the amplification refractory mutation system (ARMS). ARMS analysis was designed to detect the Dahl S AngII/AVP receptor gene variant, when present, by the production of an expected 102-bp (for the N119S substitution) and a 131-bp (for the C163R substitution) product, respectively. Analysis was done on three Dahl S (S1, S2, and S3) and two Dahl R (R1 and R2) genomic DNAs. Controls for the ARMS analysis were cloned Dahl S (S) and cloned Dahl R (R) AngII/AVPr cDNAs at four copies per genome equivalent. The 260-bp fragment corresponds to control PCR product showing equivalent amounts of cloned Dahl S and Dahl R AngII/AVPr cDNAs. The 320-bp fragment corresponds to control PCR product ascertaining that all genomic DNA samples amplify equivalently. The ARMS test readily detects G³⁵⁶ and C⁴⁸⁷ in Dahl S genomic DNA and their absence in Dahl R genomic DNA.