Does rs41272114 CC indicate absence of the low-production T allele?

The LPA gene, which encodes apolipoprotein(a), is the primary genetic determinant of circulating lipoprotein(a) [Lp(a)] levels. The rs41272114 variant is a key single nucleotide polymorphism (SNP) used to refine genetic predictions of an individual's Lp(a) profile.

Clinical and genetic findings

Evidence confirms that the rs41272114 SNP is a primary causal driver of plasma Lp(a) concentrations.

• Genotype interpretation: The CC genotype represents the wild-type or reference state. The presence of the T allele (often referred to as the minor A allele in some nomenclature) is strongly associated with significantly reduced Lp(a) levels.
• Association with Lp(a) levels: In large cohort studies, such as the Cooperative Health Research in the Region of Augsburg (KORA) F4 study, rs41272114 has been identified as a major determinant of Lp(a) variance. It is frequently included in high-accuracy predictive models alongside kringle IV type-2 (KIV-2) copy numbers to estimate serum concentrations.
• Absence of the variant: An individual with the rs41272114 CC genotype does not carry the low-production T allele. Consequently, this genotype is consistent with the "high-production" reference state at this specific locus, meaning this particular genetic brake on Lp(a) production is absent.

Mechanistic explanations

The rs41272114 T allele functions as a loss-of-function variant through the disruption of normal protein synthesis.

• Splice-site disruption: The T allele (c.4925G>A) acts as a splice-site variant. This mutation interferes with the standard mRNA splicing process, which is a critical step in the production of functional apolipoprotein(a).
• Impact on apo(a) secretion: By disrupting splicing, the T allele leads to a substantial decrease in the production and subsequent secretion of apo(a) into the plasma. This mechanism places rs41272114 in a category of variants—alongside nonsense mutations (e.g., R21X) and other splice-site mutations—that effectively lower Lp(a) levels regardless of the individual's KIV-2 copy number.

Bottom line

The rs41272114 T allele is a validated loss-of-function splice-site variant that significantly lowers Lp(a) production. Therefore, a CC genotype confirms the absence of this specific low-production allele, representing the standard-production genetic state at this locus.