rs10455872

rs10455872 is an intronic A/G variant in LPA at GRCh38 6:160589086, with the G allele at roughly 7 percent frequency in European groups and far rarer elsewhere. G tracks a shorter apolipoprotein(a) KIV-2 isoform and is the strongest single common marker of higher measured lipoprotein(a): UK Biobank median Lp(a) was about 16 to 17 nmol/L for A/A, about 127 nmol/L for A/G and about 148 to 149 nmol/L for G/G in two independent analyses. It explains only about a quarter to a third of the variation in measured Lp(a), so an A/A result cannot mean a low or normal level, and KIV-2 copy number and other LPA variants are not read by this marker. No common SNP is in strong linkage disequilibrium with it, so array-based imputation is unreliable without a direct probe.