Genotype at the P554L variant of the hexose-6 phosphate dehydrogenase gene is associated with carotid intima-medial thickness

• Published in: PloS one 2011-08, Vol.6 (8), p.e23248-e23248
• Main Authors: Rahman, Thahira J, Walker, Elizabeth A, Mayosi, Bongani M, Hall, Darroch H, Avery, Peter J, Connell, John M C, Watkins, Hugh, Stewart, Paul M, Keavney, Bernard
• Format: Article
• Language: English
• Subjects: Adipose tissue; Adult; Aged; Aged, 80 and over; Amino Acid Sequence; Amino acids; Arteriosclerosis; Atherosclerosis; Atherosclerosis - genetics; Autophagy; Biology; Carbohydrate Dehydrogenases - genetics; Cardiovascular diseases; Carotid arteries; Carotid artery; Carotid Intima-Media Thickness; Catalysis; Corticosteroids; Dehydrogenase; Dehydrogenases; Diabetes; Disease susceptibility; Endocrinology; Endoplasmic reticulum; Enzymes; Family; Family Health; Female; Gene Frequency; Gene polymorphism; Genes; Genetic aspects; Genetic Predisposition to Disease - genetics; Genotype; Genotypes; Glucocorticoids; Health risks; Heart attacks; HEK293 Cells; Hexose; Humans; Hypertension; Leucine; Linear Models; Liver; Male; Medical research; Medicine; Metabolism; Middle Aged; Molecular Sequence Data; Monosaccharides; Phenotypes; Phosphates; Physiological aspects; Polymorphism; Polymorphism, Single Nucleotide; Population genetics; Proline; Quantitative genetics; Risk analysis; Risk Factors; Sequence Homology, Amino Acid; Single nucleotide polymorphisms; Single-nucleotide polymorphism; Stroke; Studies; Tagging; Thickness measurement; Ultrasound; Variability; Veins & arteries; Young Adult
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0023248

The combined thickness of the intima and media of the carotid artery (carotid intima-medial thickness, CIMT) is associated with cardiovascular disease and stroke. Previous studies indicate that carotid intima-medial thickness is a significantly heritable phenotype, but the responsible genes are largely unknown. Hexose-6 phosphate dehydrogenase (H6PDH) is a microsomal enzyme whose activity regulates corticosteroid metabolism in the liver and adipose tissue; variability in measures of corticosteroid metabolism within the normal range have been associated with risk factors for cardiovascular disease. We performed a genetic association study in 854 members of 224 families to assess the relationship between polymorphisms in the gene coding for hexose-6 phosphate dehydrogenase (H6PD) and carotid intima-medial thickness. Families were ascertained via a hypertensive proband. CIMT was measured using B-mode ultrasound. Single nucleotide polymorphisms (SNPs) tagging common variation in the H6PD gene were genotyped. Association was assessed following adjustment for significant covariates including "classical" cardiovascular risk factors. Functional studies to determine the effect of particular SNPs on H6PDH were performed. There was evidence of association between the single nucleotide polymorphism rs17368528 in exon five of the H6PD gene, which encodes an amino-acid change from proline to leucine in the H6PDH protein, and mean carotid intima-medial thickness (p = 0.00065). Genotype was associated with a 5% (or 0.04 mm) higher mean carotid intima-medial thickness measurement per allele, and determined 2% of the population variability in the phenotype. Our results suggest a novel role for the H6PD gene in atherosclerosis susceptibility.