Novel mutations in the adipose triglyceride lipase gene causing neutral lipid storage disease with myopathy.

Abstract

A subgroup of neutral lipid storage disease has been recently associated with myopathy (NLSDM) and attributed to mutations in the gene (PNPLA2) encoding an adipose triglyceride lipase involved in the degradation of intracellular triglycerides. Five NLSDM patients have been described thus far and we reported three additional patients. A 44-year old Iranian woman and two Italian brothers, aged 40 and 35, presented with exercise intolerance and proximal limb weakness, elevated CK levels, and Jordan's anomaly. Muscle biopsies showed marked neutral lipid accumulation in all patients. The 10 exons and the intron-exon junctions of the PNPLA2 gene were sequenced. Two novel homozygous mutations in exon 5 of PNPLA2 gene were found (c.695delT and c.542delAC). Both mutations resulted in frameshifts leading to premature stop codons (p.L255X and p.I212X, respectively). These mutations predict a truncated PNPLA2 protein lacking the C-terminal hydrophobic domain. These findings indicate that NLSDM is rare, but genetically heterogeneous.

• Authors: Filomena Campagna, Luisa Nanni, Fabiana Quagliarini, Elena Pennisi, Constantine Michailidis, Francesco Pierelli, Claudio Bruno, Carlo Casali, Salvatore DiMauro, Marcello Arca
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 377 Issue 3 Pg. 843-6 (Dec 19 2008) ISSN: 1090-2104 [Electronic] United States
• PMID: 18952067 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Lipase
• PNPLA2 protein, human

Topics

• Adult
• Biopsy
• Exons (genetics)
• Female
• Frameshift Mutation
• Humans
• Lipase (genetics, metabolism)
• Lysosomal Storage Diseases, Nervous System (genetics, metabolism, pathology)
• Male
• Middle Aged
• Muscle, Skeletal (metabolism, pathology)
• Muscular Diseases (genetics, metabolism, pathology)