New mutations in the lipoprotein lipase gene in a young boy with chylomicronaemia syndrome and in his family

• Published in: Acta Paediatrica Vol. 92; no. 5; pp. 621 - 624
• Main Authors: Brites, F, Henriksen, F, Fernández, K, Brusgaard, K, Castro, G, Wikinski, R
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.05.2003; Blackwell
• Subjects: Anemia - blood; Anemia - genetics; Biological and medical sciences; Child, Preschool; Chylomicronaemia; Chylomicrons - blood; Chylomicrons - genetics; Disorders of blood lipids. Hyperlipoproteinemia; Family; Humans; hypertriglyceridaemia; lipoprotein lipase; Lipoprotein Lipase - genetics; Male; Medical sciences; Metabolic diseases; Mutation - genetics; mutations; Syndrome; Human; Enzyme; Family study; hypertriglyceridaemia; Metabolic diseases; Esterases; Lipoprotein lipase; Blood; Carboxylic ester hydrolases; Case study; Chylomicron; mutations; Gene; Hydrolases; Mutation; Child; Chylomicronaemia
• ISSN: 0803-5253; 1651-2227
• DOI: 10.1111/j.1651-2227.2003.tb02517.x

The case is reported of a 4‐y‐old boy with chylomicronaemia syndrome, under treatment with a low‐fat diet and medium‐chain triglycerides. The clinical and biochemical characteristics of the patient and 11 members of his family were studied. Lipoprotein profile, lipoprotein lipase (LPL) mass and activity were evaluated. Nucleotide substitutions in LPL promoter and exons were screened. The proband presented with severe hypertriglyceridaemia (triglycerides = 13.25 mmol l−1) and non‐detectable LPL activity and mass. The boy was a compound heterozygote for four molecular defects in the LPL gene, two of which have not been reported before (C±T764± C±T/Arg170± Leu; GG±1482± GG±Gly409± Gly). Among the family members, the proband was the only one who carried two genetic variants that modify LPL amino acid composition. Conclusion: The association of different alterations in the LPL gene could be a key factor in causing the severe phenotype observed. Moreover, treatment with a low‐fat diet and medium‐chain triglycerides failed to normalize the patient's hypertriglyceridaemia.