New mutations in the lipoprotein lipase gene in a young boy with chylomicronaemia syndrome and in his family.
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 (CGT764 CTT/Arg170 --> Leu; GGA1482 --> GGT/Gly409 --> Gly). Among the family members, the proband was the only one who carried two genetic variants that modify LPL amino acid composition.


CONCLUSIONS
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.
Brites
F
F
Laboratory of Lipids and Lipoproteins, Department of Clinical Biochemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Argentina. fbrites@dbc.ffyb.uba.ar
Henriksen
F
F
Fernández
K
K
Brusgaard
K
K
Castro
G
G
Wikinski
R
R
D000740:Anemia / Q000097:blood* / Q000235:genetics*; D002675:Child, Preschool; D002914:Chylomicrons / Q000097:blood* / Q000235:genetics*; D005190:Family; D006801:Humans; D008071:Lipoprotein Lipase / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*; D013577:Syndrome
D002914:Chylomicrons; D008071:Lipoprotein Lipase