Hypertriglyceridemia is caused not only by environmental factors but also by genetic factors. Severe
hypertriglyceridemia is prone to complications of
acute pancreatitis. Here, we report a whole-exome sequencing (WES) analysis for a young hypertriglyceridemic patient with recurrent
acute pancreatitis and the patient's mother. A 28-year-old hypertriglyceridemic female was admitted to our hospital. At 23 years old, a health checkup clarified her
hypertriglyceridemia. At the age of 26 and 27, she had repeated
acute pancreatitis with severe
hypertriglyceridemia (serum
triglyceride level were 3,888 mg/dL and 12,080 mg/dL, respectively). The patient's BMI was 29.0 kg/m2, and blood samples under
fibrate medication showed
triglyceride 451 mg/dL and HbA1c 7.2%. Type V
dyslipidemia became more apparent at postprandial state. The WES analysis showed that the patients had two heterozygous variants in
Apolipoprotein A5 (APOA5) gene (p.G185C and p.V153M), a heterozygous variant in
Apolipoprotein E (
APOE) gene (p.R176C), three heterozygous variants in
Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene (p.T1220I, p.R1453W and p.V470M). On the other hand, her mother, who had moderate
hypertriglyceridemia without
acute pancreatitis, had a heterozygous variant in APOA5 gene (p.G185C) and two heterozygous variants in CFTR gene (p.T1220I and p.V470M). These results suggest that the more severe pathology of the patient than her mother might be due to the possible compound heterozygous APOA5 variants, the heterozygous
APOE variant, and the possible compound heterozygous CFTR variants. In this case, WES analyses were useful to evaluate not only the causative genes of
hypertriglyceridemia (APOA5 and
APOE) but also the genes involved in the development of
acute pancreatitis (CFTR) simultaneously.