Liver Adiposity Effects on Pediatric Statin

Inclusion Criteria:

* 8-21 years
* LDL cholesterol \>130mg/dl (\>95% percentile)
* SLCO1B1 c.521TT genotype
* Provide informed permission-assent(\<18 yrs.) or consent (≥18 yrs.)
* Fasting overnight (\~8 hrs.)
* Enrolled in Cardiology Pharmacogenomic Repository

Exclusion Criteria:

* Pregnancy
* Non-fasting
* Non-removable metal in body or MRI unsafe
* Currently on statin therapy and unwilling to wash out of statin therapy for at least 4 weeks prior to Visit 1 and throughout the duration of the study.
* Underlying unrepaired congenital or acquired cardiovascular defects or repaired congenital or acquired cardiovascular defects with hemodynamically significant residual disease.
* History of underlying or laboratory evidence of underlying intestinal, metabolic, autoimmune, renal disease that can alter rosuvastatin disposition\* (absorption, metabolism, distribution, or clearance)
* Pharmacotherapy that interacts with statins (OATP1B1 inducers/inhibitors) \*
* Inability to swallow a tablet
* \>5x the age-specific upper limit of normal for AST, ALT, total and conjugated bilirubin
* Diarrhea in the last 24 hours
* Anything that would exclude a participant from completing an MRI, such as pacemakers, claustrophobia, or body habitus (e.g., weight greater than 350 lbs.)