Myocardial infarction in a 36-year-old man with combined ABCA1 and APOA-1 deficiency

•We present an extremely young patient with myocardial infarction and high-density lipoprotein cholesterol deficiency.•The high-density lipoprotein deficiency is caused by a unique combination of ABCA1 and APOA1 mutations.•Both mutations lead to a well-characterized reduction in reverse cholesterol transport.•Combined genetic cholesterol efflux impairment contributes to premature atherosclerosis.

In this report, we present a patient who suffered from a myocardial infarction at an extremely young age. The only remarkable finding in the risk factor workup was a near undetectable high-density lipoprotein (HDL)-cholesterol plasma level (0.09 mmol/L). Genetic analysis of key genes involved in HDL metabolism resulted in the discovery of 2 very rare mutations in the ABCA1 and APOA1 genes. We discuss the effects of these mutations on HDL metabolism and reverse cholesterol transport and interpret these findings in relation to the extensive atherosclerosis at a very young age in this patient.