SCARB1 encodes scavenger receptor class B type 1 (SR‑BI), a membrane receptor expressed in liver, steroidogenic tissues, and vascular cells that mediates selective uptake of cholesteryl esters from HDL. Biochemically, SR‑BI is part of lipid transport and reverse cholesterol transport pathways that move cholesterol between tissues and plasma lipoproteins. The specific markers rs4238001 and rs5888 are single‑nucleotide polymorphisms (SNPs) that have been studied in population and functional research. Early genetic and animal studies established SR‑BI’s central role in cholesterol clearance and HDL biology; human SNP studies have linked these variants to measurable differences in HDL metrics, lipid particle characteristics, and related biomarkers, without implying a deterministic outcome for any individual.

Variants that are associated with reduced SCARB1 expression or function (a functional “low”) have been linked in studies to altered HDL measures—sometimes higher circulating HDL cholesterol but changes in HDL quality or cholesterol transport efficiency—and shifts in other lipid parameters. Variants associated with relatively greater SCARB1 activity (a functional “high”) may correlate with more efficient HDL‑mediated cholesterol uptake and different lipid profiles. Genetic associations are one piece of the picture: interpretation is most informative when combined with the Cardio Zoomer’s lipid, inflammation, metabolic, and vascular markers, as well as clinical and lifestyle context.

SCARB1 variants are included in Cardio Zoomer to add inherited context to lipid handling and HDL function. Knowing genotype-associated tendencies helps clinicians interpret discordant lipid results, understand possible mechanisms behind abnormal lipid markers, and integrate genetic influence with biomarkers like ApoB, Lp(a), ceramides, and inflammatory signals to personalize assessment.