47 research outputs found
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Genetic analysis of a major international collection of cultivated apple varieties reveals previously unknown historic heteroploid and inbred relationships
Domesticated apple (Malus x domestica Borkh.) is a major global crop and the genetic diversity held within the pool of cultivated varieties is important for the development of future cultivars. The aim of this study was to investigate the diversity held within the domesticated form, through the analysis of a major international germplasm collection of cultivated varieties, the UK National Fruit Collection, consisting of over 2,000 selections of named cultivars and seedling varieties. We utilised Diversity Array Technology (DArT) markers to assess the genetic diversity within the collection. Clustering attempts, using the software STRUCTURE revealed that the accessions formed a complex and historically admixed group for which clear clustering was challenging. Comparison of accessions using the Jaccard similarity coefficient allowed us to identify clonal and duplicate material as well as revealing pairs and groups that appeared more closely related than a standard parent-offspring or full-sibling relations. From further investigation, we were able to propose a number of new pedigrees, which revealed that some historically important cultivars were more closely related than previously documented and that some of them were partially inbred. We were also able to elucidate a number of parent-offspring relationships that had resulted in a number of important polyploid cultivars. This included reuniting polyploid cultivars that in some cases dated as far back as the 18th century, with diploid parents that potentially date back as far as the 13th century
Using genetic information from candidate gene and genome-wide association studies in risk prediction for alcohol dependence
Family-based and genome-wide association studies (GWAS) of alcohol dependence (AD) have reported numerous associated variants. The clinical validity of these variants for predicting AD compared with family history information has not been reported. Using the Collaborative Study on the Genetics of Alcoholism (COGA) and the Study of Addiction: Genes and Environment (SAGE) GWAS samples, we examined the aggregate impact of multiple single nucleotide polymorphisms (SNPs) on risk prediction. We created genetic sum scores by adding risk alleles associated in discovery samples, and then tested the scores for their ability to discriminate between cases and controls in validation samples. Genetic sum scores were assessed separately for SNPs associated with AD in candidate gene studies and SNPs from GWAS analyses that met varying P-value thresholds. Candidate gene sum scores did not exhibit significant predictive accuracy. Family history was a better classifier of case-control status, with a significant area under the receiver operating characteristic curve (AUC) of 0.686 in COGA and 0.614 in SAGE. SNPs that met less stringent P-value thresholds of 0.01-0.50 in GWAS analyses yielded significant AUC estimates, ranging from mean estimates of 0.549 for SNPs with P < 0.01 to 0.565 for SNPs with P < 0.50. This study suggests that SNPs currently have limited clinical utility, but there is potential for enhanced predictive ability with better understanding of the large number of variants that might contribute to risk
Intraocular cytokine profile and autoimmune reactions in retinitis pigmentosa, age-related macular degeneration, glaucoma and cataract
Purpose: To analyse intraocular cytokine levels and prevalence of intraocular antiretinal antibodies (ARAs) in patients with retinitis pigmentosa (RP), age-related macular degeneration (AMD), glaucoma and cataract, and correlate the results to clinical manifestations. Methods: We collected intraocular fluid samples from patients with RP (n = 25), AMD (n = 12), glaucoma (n = 28) and cataract (n = 22), and serum samples paired with the intraocular fluids from patients with RP (N = 7) and cataract (n = 10). Interleukin (IL)-1β, IL-1ra, IL-2, IL-6, IL-6rα, IL-7, IL-8, IL-10, IL-17A, IL-23, thymus- and activation-regulated chemokine (TARC), monocyte chemoattractant protein-1 (MCP-1), tumour necrosis factor-alpha (TNF-α), placental growth factor (PlGF) and vascular endothelial growth factor (VEGF) were measured using a multiplex assay. Antiretinal antibodies (ARA) detection was performed by indirect immunofluorescence. Results: Increasing age was associated with increasing levels of IL-6, IL-8, TNF-α and VEGF. All patient groups exhibited distinct profiles of intraocular cytokines. Intraocular levels of IL-8 were highest in patients with AMD and glaucoma. Cataract patients exhibited high intraocular levels of IL-23. Intraocular levels of IL-2, IL-6, MCP-1 and PlGF in RP patients exceeded the levels of serum, indicating intraocular production. Intraocular ARAs were found in only one patient with AMD. Conclusion: Increased levels of inflammatory cytokines in intraocular fluid of patients with originally noninflammatory ocular diseases show that intraocular inflammation is involved in their pathogenesis of these entities. Moreover, we show that increasing age is associated with increasing levels of intraocular cytokines and conclude that future studies on intraocular mediators should be corrected for age of patients
Infrared vibrational spectroscopy: a rapid and novel diagnostic and monitoring tool for cystinuria
Cystinuria is the commonest inherited cause of nephrolithiasis (~1% in adults; ~6% in children) and is the result of impaired cystine reabsorption in the renal proximal tubule. Cystine is poorly soluble in urine with a solubility of ~1 mM and can readily form microcrystals that lead to cystine stone formation, especially at low urine pH. Diagnosis of cystinuria is made typically by ion-exchange chromatography (IEC) detection and quantitation, which is slow, laboursome and costly. More rapid and frequent monitoring of urinary cystine concentration would significantly improve the diagnosis and clinical management of cystinuria. We used attenuated total reflection - Fourier transform infrared spectroscopy (ATR-FTIR) to detect and quantitate insoluble cystine in 22 cystinuric and 5 healthy control urine samples. Creatinine concentration was also determined by ATR-FTIR to adjust for urinary concentration/dilution. Urine was centrifuged, the insoluble fraction re-suspended in 5 μL water and dried on the ATR prism. Cystine was quantitated using its 1296 cm−1 absorption band and levels matched with parallel measurements made using IEC. ATR-FTIR afforded a rapid and inexpensive method of detecting and quantitating insoluble urinary cystine. This proof-of-concept study provides a basis for developing a high-throughput, cost-effective diagnostic method for cystinuria, and for point-of-care clinical monitoring
An Intraocular Inflammatory Profile of Rubella Associated Uveitis
Purpose: To analyze intraocular cytokine levels and cell profiles in patients with rubella virus-associated uveitis (RVU). Methods: We collected intraocular fluid samples from patients with RVU (n = 10), uveitis of other causes (n = 27), and cataract (n = 22). Levels of 15 cytokines (IL-1β, IL-1ra, IL-2, IL-6, IL-6rα, IL-7, IL-8, IL-10, IL-17A, IL-23, TARC, MCP-1, TNF-α, PlGF, and VEGF) were measured using multiplex assay, and i
Unsubstituted and Hydroxy Substituted Fatty Acids in a Recent Lacustrine Sediment (Lake Léman, Geneva, Switzerland)
Unsubstituted as well as α-, β- and (ω-1)-hydroxy substituted fatty acids were analyzed in a 5 m long sediment core taken from Lake Léman (Switzerland). All these acids occur in three forms: unbound, bound and tightly bound and our results show that there is no conversion from one form to another. The fact that below a burial depth of 30 cm the abundance profiles show no decreasing trend indicates that the diagenetic reactions do not operate below that depth. On the basis of our results, compared with other published data, source correlations are postulated for each of the acid classes. The presence of unsubstituted monounsaturated acids in the C₂₀ to C₃₂ range probably indicates that long chain fatty acids cannot be considered only as indicators of inputs from higher plants. Finally, C₂₇, C₂₉ and C₃₁ (ω-1)-hydroxyacids with unusual structures have also been found in these sediments, as well as 2-methyl nonacosanoic acid; their origin has not yet been established