Genotyping of Essential Hypertension Single-Nucleotide Polymorphisms by a Homogeneous PCR Method with Universal Energy Transfer Primers

• Published in: Clinical chemistry (Baltimore, Md.) Vol. 48; no. 12; pp. 2131 - 2140
• Main Authors: Bengra, Chikh, Mifflin, Theodore E, Khripin, Yuri, Manunta, Paolo, Williams, Scott M, Jose, Pedro A, Felder, Robin A
• Format: Journal Article
• Language: English
• Published: Washington, DC Am Assoc Clin Chem 01.12.2002; American Association for Clinical Chemistry; Oxford University Press
• Subjects: Angiotensinogen - genetics; Biological and medical sciences; Cloning; Cytochrome P-450 CYP11B2 - genetics; Disease; DNA Primers; Energy transfer; Fluorescence Resonance Energy Transfer; Fluorometry; G-Protein-Coupled Receptor Kinase 4; Genes; Genetic screening; Genetic testing; Genomes; Genotype; Genotypes; Humans; Hypertension; Hypertension - genetics; Investigative techniques, diagnostic techniques (general aspects); Kinases; Medical sciences; Methods; Miscellaneous. Technology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Polymerase Chain Reaction - methods; Polymorphism, Single Nucleotide; Protein-Serine-Threonine Kinases - genetics; Human; Hypertension; Primer; Cardiovascular disease; Essential; Vascular disease; Polymerase chain reaction; Cytogenetics; Diagnosis; Single nucleotide polymorphism; Technique; Molecular biology; Energy transfer
• ISSN: 0009-9147; 1530-8561
• DOI: 10.1093/clinchem/48.12.2131

Human hypertension is a complex, multifactorial disease with a heritability of more than 30-50%. A genetic screening test based on analysis of multiple single-nucleotide polymorphisms (SNPs) to assess the likelihood of developing hypertension would be helpful for disease management. Tailed allele-specific primers were designed to amplify by PCR six biallelic SNP loci [three in G protein-coupled receptor kinase type 4 (GRK4): R65L, A142V, and A486V; two in angiotensinogen: -6G-->A and M235T; and one in aldosterone synthase: -344C-->T] associated with essential hypertension. PCRs of SNP loci were coupled (via a common sequence of 21 nucleotide tails) to incorporate Universal Amplifluor(TM) primers labeled with fluorescein or sulforhodamine in a homogeneous format. Use of Amplifluors in SNP PCRs produced labeled amplicons, the fluorescence of which was quantified by a microplate reader and then analyzed via an Excel macro to provide genotypes for all six SNP loci. Unique restriction endonucleases were identified for five SNP loci that could independently confirm homogeneous PCR results when needed. We developed six homogeneous PCR assays that were set up, performed, and fluorometrically analyzed in 96-well microplates. Allele frequencies were determined for six SNPs in 60 Italian hypertensive patients and a control group of 60 normotensive persons. A significant correlation (P = 0.034) between one SNP [GRK4 (A486V)] and the hypertensive patients was observed. Genotyping results for five of six SNPs were confirmed by digesting corresponding amplicons with locus-specific restriction endonucleases. We developed a simple and homogeneous fluorescent protocol that has been used to determine the SNP genotype for six loci in a population of hypertensive and normotensive persons. We also observed a significant association (P = 0.034) between one SNP (A486V) and an Italian population of mildly hypertensive patients.