CST3 and chronic kidney disease: Li et al. utilised the same genetic instrument in a UK Biobank cohort to reveal that genetically-determined telomere attrition did not affect the risk of diseases such as diabetes or CKD [47]; however, Park et al. highlighted that this null result may be due to the low number of self-reported or ICD-confirmed diagnosis for CKD and instead opted for serum cystatin C and creatinine level classification [50].