Rare LPL gene missense mutation in an infant with hypertriglyceridemia

Abstract

Background: Severe hypertriglyceridemia usually results from a combination of genetic and environmental factors and is most often attributable to mutations in the lipoprotein lipase (LPL) gene.

Objectives: The aim of this study was to identify rare mutations in the LPL gene causing severe hypertriglyceridemia.

Methods: A Chinese infant who presented classical features of severe hypertriglyceridemia recruited for DNA sequencing of the LPL gene. The pathogenicity grade of the variants was defined based on the prediction of pathogenicity using in silico prediction tools. Review some studies to understand the molecular mechanisms underlying the severe hypertriglyceridemia.

Results: We identified a rare mutation in the LPL gene causing severe hypertriglyceridemia: a nucleotide substitution (c.836T>G) resulting in a leucine to arginine substitution at position 279 of the protein (p.Leu279Arg).The pathogenicity of the variant was predicted by in silico analysis using PolyPhen2 and SIFT prediction programs, which indicated that mutation p.Leu279Arg is probably harmful. We have also reviewed published studies concerning the molecular mechanisms underlying severe hypertriglyceridemia. A missense mutation in the 6 exon of the LPL gene is reportedly associated with LPL deficiency.

Conclusions: We have here identified a rare pathogenic mutation in the LPL gene in a Chinese infant with severe hypertriglyceridemia.

Keywords: Hypertriglyceridemia; LPL gene; heterozygous; missense.

Figure 1

Pedigree of the reported family. The proband is indicated by an arrow. Half‐filled symbols denote affected individuals, carriers of the mutation p.Leu279Arg of the LPL gene, and empty symbols denote noncarriers

Figure 2

Sequence analysis of the LPL mutations. Upper panel: segments of genomic DNA sequences of the proband showing a nucleotide substitution (c.836T>G) in the region indicated by the red arrows. Lower panel: segments of genomic DNA sequences of the control individual (the proband's mother); his father and sister were found to be heterozygous carriers of c.836T>G missense mutations

Figure 3

Partial amino acid sequences of LPL in 11 species were compared. A highly conserved p.L279 leucine sequence is present in these 11 species (black)