Association of an ACSL1 gene variant with polyunsaturated fatty acids in bovine skeletal muscle

<p>Abstract</p> <p>Background</p> <p>The intramuscular fat deposition and the fatty acid profiles of beef affect meat quality. High proportions of unsaturated fatty acids are related to beef flavor and are beneficial for the nutritional value of meat. Moreover, a variety of clinical and epidemiologic studies showed that particularly long-chain omega-3 fatty acids from animal sources have a positive impact on human health and disease.</p> <p>Results</p> <p>To screen for genetic factors affecting fatty acid profiles in beef, we initially performed a microsatellite-based genome scan in a F₂Charolais × German Holstein resource population and identified a quantitative trait locus (QTL) for fatty acid composition in a region on bovine chromosome 27 where previously QTL affecting marbling score had been detected in beef cattle populations. The <it>long-chain acyl-CoA synthetase 1 (ACSL1) </it>gene was identified as the most plausible functional and positional candidate gene in the QTL interval due to its direct impact on fatty acid metabolism and its position in the QTL interval. ACSL1 is necessary for synthesis of long-chain acyl-CoA esters, fatty acid degradation and phospholipid remodeling. We validated the genomic annotation of the bovine <it>ACSL1 </it>gene by <it>in silico </it>comparative sequence analysis and experimental verification. Re-sequencing of the complete coding, exon-flanking intronic sequences, 3' untranslated region (3'UTR) and partial promoter region of the <it>ACSL1 </it>gene revealed three synonymous mutations in exons 6, 7, and 20, six noncoding intronic gene variants, six polymorphisms in the promoter region, and four variants in the 3' UTR region. The association analysis identified the gene variant in intron 5 of the <it>ACSL1 </it>gene (<it>c.481-233A>G</it>) to be significantly associated with the relative content of distinct fractions and ratios of fatty acids (e.g., n-3 fatty acids, polyunsaturated, n-3 long-chain polyunsaturated fatty acids, trans vaccenic acid) in skeletal muscle. A tentative association of the <it>ACSL1 </it>gene variant with intramuscular fat content indicated that an indirect effect on fatty acid composition via modulation of total fat content of skeletal muscle cannot be excluded.</p> <p>Conclusions</p> <p>The initial QTL analysis suggested the <it>ACSL1 </it>gene as a positional and functional candidate gene for fatty acid composition in bovine skeletal muscle. The findings of subsequent association analyses indicate that <it>ACSL1 </it>or a separate gene in close proximity might play a functional role in mediating the lipid composition of beef.</p

Serum Ascorbic Acid and Thiamine Concentrations in Sepsis: Secondary Analysis of the Swiss Pediatric Sepsis Study.

OBJECTIVES To determine circulating levels of ascorbic acid (VitC) and thiamine (VitB1) in neonates and children with blood culture-proven sepsis. DESIGN Nested single-center study of neonates and children prospectively included in the Swiss Pediatric Sepsis Study. SETTING One tertiary care academic hospital. PATIENTS Sixty-one neonates and children 0-16 years old. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS VitC and VitB1 were quantified in serum of patients (median age, 10.5 mo; interquartile range [IQR], 0.5-62.1 mo) with blood culture-proven sepsis. Median time between sepsis onset and sampling for measurement of vitamins was 3 days (IQR, 2-4 d). Median serum levels of VitC and VitB1 were 32.4 μmol/L (18.9-53.3 μmol/L) and 22.5 nmol/L (12.6-82 nmol/L); 36% of the patients (22/61) had low VitC and 10% (6/61) had VitC deficiency; and 72% (44/61) had low VitB1 and 13% (8/61) had VitB1 deficiency. Children with low VitC were older (p = 0.007) and had higher C-reactive protein (p = 0.004) compared with children with VitC within the normal range. Children with low VitB1 levels were older (p = 0.0009) and were less frequently receiving enteral or parenteral vitamin supplementation (p = 0.0000003) compared with children with normal VitB1 levels. CONCLUSIONS In this cohort of newborns and children with sepsis, low and deficient VitC and VitB1 levels were frequently observed. Age, systemic inflammation, and vitamin supplementation were associated with vitamin levels during sepsis

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder