Genetic determinants of statin intolerance.

Background: Statin-related skeletal muscle disorders range from benign myalgias--such as non-specific muscle aches or joint pains without elevated serum creatinine kinase (CK) concentration--to true myositis with >10-fold elevation of serum CK, to rhabdomyolysis and myoglobinuria. The genetic basis of statin-related muscle disorders is largely unknown. Because mutations in the COQ2 gene are associated with severe inherited myopathy, we hypothesized that common, mild genetic variation in COQ2 would be associated with inter-individual variation in statin intolerance.

Quantitative and qualitative differences in subcutaneous adipose tissue stores across lipodystrophy types shown by magnetic resonance imaging.

Background: Lipodystrophies are characterized by redistributed subcutaneous fat stores. We previously quantified subcutaneous fat by magnetic resonance imaging (MRI) in the legs of two patients with familial partial lipodystrophy subtypes 2 and 3 (FPLD2 and FPLD3, respectively). We now extend the MRI analysis across the whole body of patients with different forms of lipodystrophy.

Semi-automated segmentation and quantification of adipose tissue in calf and thigh by MRI: a preliminary study in patients with monogenic metabolic syndrome.

Background: With the growing prevalence of obesity and metabolic syndrome, reliable quantitative imaging methods for adipose tissue are required. Monogenic forms of the metabolic syndrome include Dunnigan-variety familial partial lipodystrophy subtypes 2 and 3 (FPLD2 and FPLD3), which are characterized by the loss of subcutaneous fat in the extremities. Through magnetic resonance imaging (MRI) of FPLD patients, we have developed a method of quantifying the core FPLD anthropometric phenotype, namely adipose tissue in the mid-calf and mid-thigh regions.

Treatment of dyslipidemia with lovastatin and ezetimibe in an adolescent with cholesterol ester storage disease.

Background: Cholesterol ester storage disease (CESD) is an autosomal recessive illness that results from mutations in the LIPA gene encoding lysosomal acid lipase. CESD patients present in childhood with hepatomegaly and dyslipidemia characterized by elevated total and low-density lipoprotein cholesterol (LDL-C), with elevated triglycerides and depressed high-density lipoprotein cholesterol (HDL-C). Usual treatment includes a low fat diet and a statin drug.

Optimizing RNA extraction yield from whole blood for microarray gene expression analysis.

Objectives: Microarray analysis of gene expression profiles of blood leukocytes has many potential clinical and research applications.

Design And Methods: We used the PAXgene Blood RNA System to prepare RNA from the whole blood of normal volunteers using two incubation times followed by gene expression profiling using the Affymetrix HU133A GeneChip.

Conclusions: Longer incubation gave a significantly higher RNA yield and samples that were satisfactory for microarray analysis, with excellent pairwise correlations between replicates.

Assembly and secretion of very low density lipoproteins containing apolipoprotein B48 in transfected McA-RH7777 cells. Lack of evidence that palmitoylation of apolipoprotein B48 is required for lipoprotein secretion.

We examined the role of S-linked palmitoylation of human apolipoprotein (apo) B in the assembly and secretion of very low density lipoproteins using recombinant human apoB48. There are four free cysteine residues (Cys(1085), Cys(1396), Cys(1478), and Cys(1635)) within apoB48 that potentially can be palmitoylated. All four cysteine residues were substituted with serine by site-specific mutagenesis.

A novel nontruncating APOB gene mutation, R463W, causes familial hypobetalipoproteinemia.

Familial hypobetalipoproteinemia (FHBL), an autosomal co-dominant disorder, is associated with reduced plasma concentrations (<5th percentile for age and sex) of apolipoprotein (apo) B and beta-migrating lipoproteins. To date, only mutations in APOB encoding prematurely truncated apoB have been found in FHBL. We discovered a novel APOB gene mutation, namely R463W, in an extended Christian Lebanese FHBL kindred.

Elevated serum C-reactive protein and free fatty acids among nondiabetic carriers of missense mutations in the gene encoding lamin A/C (LMNA) with partial lipodystrophy.

Objective: Dunnigan-type familial partial lipodystrophy (FPLD) due to mutant LMNA is a monogenic form of insulin resistance. Affected subjects, especially women, are at increased risk of early coronary heart disease (CHD). Although common insulin resistance is associated with several biochemical perturbations, including elevated C-reactive protein (CRP), the biochemical profile in subjects with mutant LMNA is incompletely defined.

Functional promoter polymorphism in SREBP cleavage-activating protein (SCAP).

We report the identification of a loss-of-function -11C>T promoter mutation in the gene encoding the sterol regulatory element binding protein cleavage-activating protein (SCAP). The -11T allele was associated with a marked reduction in promoter activity in a luciferase-based expression system. We also report additional common single-nucleotide polymorphisms in the SCAP promoter and coding sequence that were identified by using direct sequencing to screen the genomic DNA of subjects with combined hyperlipidemia.