1. Frequent LPA KIV-2 Variants Lower Lipoprotein(a) Concentrations and Protect Against Coronary Artery Disease
- Author
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Schachtl-Riess, Johanna F., Kheirkhah, Azin, Grüneis, Rebecca, Di Maio, Silvia, Schoenherr, Sebastian, Streiter, Gertraud, Losso, Jamie Lee, Paulweber, Bernhard, Eckardt, Kai-Uwe, Köttgen, Anna, Lamina, Claudia, Kronenberg, Florian, Coassin, Stefan, For The GCKD Investigators, Meiselbach, Heike, Schneider, Markus P., Schiffer, Mario, Prokosch, Hans-Ulrich, Bärthlein, Barbara, Beck, Andreas, Reis, André, Ekici, Arif B., Becker, Susanne, Becker-Grosspitsch, Dinah, Alberth-Schmidt, Ulrike, Hausknecht, Birgit, Weigel, Anke, Walz, Gerd, Schultheiß, Ulla T., Kotsis, Fruzsina, Meder, Simone, Mitsch, Erna, Reinhard, Ursula, Floege, Jürgen, Saritas, Turgay, Schaeffner, Elke, Baid-Agrawal, Seema, Theisen, Kerstin, Haller, Hermann, Menne, Jan, Zeier, Martin, Sommerer, Claudia, Theilinger, Johanna, Wolf, Gunter, Busch, Martin, Paul, Rainer, Sitter, Thomas, Wanner, Christoph, Krane, Vera, Börner-Klein, Antje, Bauer, Britta, Raschenberger, Julia, Kollerits, Barbara, Forer, Lukas, Schönherr, Sebastian, Weissensteiner, Hansi, Oefner, Peter J., Gronwald, Wolfram, Schmid, Matthias, and Nadal, Jennifer
- Subjects
medicine.medical_specialty ,610 Medizin ,Coronary Artery Disease ,Mendelian randomization ,cardiovascular disease ,cohort study ,copy number variation ,genetic variability ,lipoprotein(a) ,Coronary artery disease ,Kringles ,Internal medicine ,Medicine ,Humans ,Copy-number variation ,Genetic variability ,Prospective Studies ,Risk factor ,ddc:610 ,biology ,business.industry ,Genetic Variation ,Lipoprotein(a) ,medicine.disease ,biology.protein ,Cardiology ,lipids (amino acids, peptides, and proteins) ,biological phenomena, cell phenomena, and immunity ,Cardiology and Cardiovascular Medicine ,business ,Lipoprotein ,Cohort study - Abstract
Background: Lipoprotein(a) (Lp(a)) concentrations are a major independent risk factor for coronary artery disease (CAD) and are mainly determined by variation in LPA. Up to 70% of the LPA coding sequence is located in the hypervariable kringle IV type 2 (KIV-2) region. It is hardly accessible by conventional technologies, but may contain functional variants. Objectives: This study sought to investigate the new, very frequent splicing variant KIV-2 4733G>A on Lp(a) and CAD. Methods: We genotyped 4733G>A in the GCKD (German Chronic Kidney Disease) study (n = 4,673) by allele-specific polymerase chain reaction, performed minigene assays, identified proxy single nucleotide polymorphisms and used them to characterize its effect on CAD by survival analysis in UK Biobank (n = 440,234). Frequencies in ethnic groups were assessed in the 1000 Genomes Project. Results: The 4733G>A variant (38.2% carrier frequency) was found in most isoform sizes. It reduces allelic expression without abolishing protein production, lowers Lp(a) by 13.6 mg/dL (95% CI: 12.5-14.7; P < 0.0001) and is the strongest variance-explaining factor after the smaller isoform. Splicing of minigenes was modified. Compound heterozygosity (4.6% of the population) for 4733G>A and 4925G>A, another KIV-2 splicing mutation, reduces Lp(a) by 31.8 mg/dL and most importantly narrows the interquartile range by 9-fold (from 42.1 to 4.6 mg/dL) when compared to the wild type. In UK Biobank 4733G>A alone and compound heterozygosity with 4925G>A reduced HR for CAD by 9% (95% CI: 7%-11%) and 12% (95% CI: 7%-16%) (both P < 0.001). Frequencies in ethnicities differ notably. Conclusions: Functional variants in the previously inaccessible LPA KIV-2 region cooperate in determining Lp(a) variance and CAD risk. Even a moderate but lifelong genetic Lp(a) reduction translates to a noticeable CAD risk reduction.
- Published
- 2021