Low polymorphism revealed in new microsatellite markers for Bemisia tabaci (Hemiptera: Aleyrodidae)

The silverleaf whitefly (Bemisia tabaci) is actually a complex of morphologically indistinct species that vary in their capacity to transmit plant viruses and to induce physiological disorders in plants of economic importance. The worldwide impact of this whitefly has increased greatly, as it is a vector of various types of phytovirus, especially geminiviruses, in plants of economic importance. The adaptability of B. tabaci to many regions of the world has fostered the appearance of various biotypes that attack a broad spectrum of host plants. We developed microsatellite markers to study genetic variability and population structure of this whitefly in Brazil. Thirteen polymorphic microsatellite markers were isolated and characterized in 20 individuals from a natural population that were collected in soybean in Campinas (SP). The number of alleles per locus ranged from one to two, and the expected heterozygosity ranged from 0.000 to 0.505. These microsatellite markers will be useful for studies and management of B. tabaci. The low polymorphism found in these molecular markers is probably associated with homology of genes expressed in these markers.

Application of Microsatellite Primers Developed for Polistes in the Independent-Founding Wasp Polists satan Bequaert (Hymenoptera: Vespidae)

Microsatellite primers developed for a given species are sometimes useful for another in the same genus and in other genera within the same family, making possible to search for pre-existing suitable primers in the databanks such as GenBank. We examined whether existing primers developed for Polistes could be used for Polistes satan Bequaert. We tested 50 microsatellite primers from three Polistes species and found that six microsatellite loci show polymorphism in size in P. satan. These six loci were highly polymorphic, having four to 15 alleles in P. satan with an expected heterozygosity of 0.525-0.832. These loci can be used to study parameters concerning genetic relatedness such as social interactions in colonies and genetic conflicts of interest among nestmate individuals.

Evaluation of MLH1 I219V Polymorphism in Unrelated South American Individuals Suspected of Having Lynch Syndrome

Background: Some single-nucleotide polymorphisms are associated with higher risk of colorectal cancer development and are suggested to explain part of the genetic contribution to Lynch syndrome. Aim: To evaluate the mutL homolog 1 (MLH1) I219V polymorphism in 124 unrelated South American individuals suspected of having Lynch syndrome, based on frequency, association with pathogenic MLH1 and mutS homolog 2 (MSH2) mutation and clinical features. Materials and Methods: DNA was obtained from peripheral blood and polymerase chain reaction (PCR) was performed, followed by direct sequencing. Results: The Val allelic of the I219V polymorphism was found in 51.61% (64/124) of the individuals, with an allelic frequency of 0.3. MLH1 or MHS2 pathogenic mutations were found in 32.81% (21/64) and in 23.33% (14/60) of Val-carriers and non-carriers, respectively. Conclusion: The Val-carrying genotype was frequent in the studied population; however, it does not appear to exert any modifier effect on MLH1 or MSH2 pathogenic mutations and the development of colorectal cancer.

MICROSATELLITE LOCI FOR TUCUMA OF AMAZONAS (ASTROCARYUM ACULEATUM) AND AMPLIFICATION IN OTHER ARECACEAE

Premise of the study: Microsatellite loci were developed for tucuma of Amazonas (Astrocaryum aculeatum), and cross-species amplification was performed in six other Arecaceae, to investigate genetic diversity and population structure and to provide support for natural populations management. Methods and Results: Fourteen microsatellite loci were isolated from a microsatellite-enriched genomic library and used to characterize two wild populations of tucuma of Amazonas (Manaus and Manicore cities). The investigated loci displayed high polymorphism for both A. aculeatum populations, with a mean observed heterozygosity of 0.498. Amplification rates ranging from 50% to 93% were found for four Astrocaryum species and two additional species of Arecaceae. Conclusions: The information derived from the microsatellite markers developed here provides significant gains in conserved allelic richness and supports the implementation of several molecular breeding strategies for the Amazonian tucuma.

DEVELOPMENT OF MICROSATELLITE MARKERS FOR QUALEA GRANDIFLORA (VOCHYSIACEAE), A TYPICAL SPECIES OF THE BRAZILIAN CERRADO

Premise of the study: Microsatellite primers were developed to investigate genetic diversity and population structure of Qualea grandiflora, a typical species of the Brazilian cerrado. Methods and Results: Eight microsatellite loci were isolated using an enrichment cloning protocol. These loci were tested on a population of 110 individuals of Q. grandiflora collected from a cerrado fragment in Sao Paulo State, Brazil. The loci polymorphism ranges from seven to 19 alleles and the average heterozygosity value is 0.568, while the average polymorphic information content is 0.799. Conclusions: The developed markers were found to be highly polymorphic, indicating their applicability to studies of population genetic diversity in Q. grandiflora

Growth hormone pharmacogenetics: the interactive effect of a microsatellite in the IGF1 promoter region with the GHR-exon 3 and-202 A/C IGFBP3 variants on treatment outcomes of children with severe GH deficiency

Insulin-like growth factor type 1 (IGF1) is a mediator of growth hormone (GH) action, and therefore, IGF1 is a candidate gene for recombinant human GH (rhGH) pharmacogenetics. Lower serum IGF1 levels were found in adults homozygous for 19 cytosine-adenosine (CA) repeats in the IGF1 promoter. The aim of this study was to evaluate the influence of (CA)n IGF1 polymorphism, alone or in combination with GH receptor (GHR)-exon 3 and -202 A/C insulin-like growth factor binding protein-3 (IGFBP3) polymorphisms, on the growth response to rhGH therapy in GH-deficient (GHD) patients. Eighty-four severe GHD patients were genotyped for (CA) n IGF1, -202 A/C IGFBP3 and GHR-exon 3 polymorphisms. Multiple linear regressions were performed to estimate the effect of each genotype, after adjustment for other influential factors. We assessed the influence of genotypes on the first year growth velocity (1st y GV) (n = 84) and adult height standard deviation score (SDS) adjusted for target-height SDS (AH-TH SDS) after rhGH therapy (n = 37). Homozygosity for the IGF1 19CA repeat allele was negatively correlated with 1st y GV (P = 0.03) and AH-TH SDS (P = 0.002) in multiple linear regression analysis. In conjunction with clinical factors, IGF1 and IGFBP3 genotypes explain 29% of the 1st y GV variability, whereas IGF1 and GHR polymorphisms explain 59% of final height-target-height SDS variability. We conclude that homozygosity for IGF1 (CA) 19 allele is associated with less favorable short-and long-term growth outcomes after rhGH treatment in patients with severe GHD. Furthermore, this polymorphism exhibits a non-additive interaction with -202 A/C IGFBP3 genotype on the 1st y GV and with GHR-exon 3 genotype on adult height. The Pharmacogenomics Journal (2012) 12, 439-445; doi:10.1038/tpj.2011.13; published online 5 April 2011

New microsatellite markers for garlic, Allium sativum (Alliaceae)

Premise of the study: A new set of microsatellite or simple sequence repeat (SSR) markers for garlic, an important medicinal spice, was developed to aid studies of genetic diversity and to define efficient strategies for germplasm conservation. Methods and Results: Using a (CT)(8)- and (GT)(8)-enriched library, a total of 16 SSR loci were developed and optimized in garlic. Ten loci were found to be polymorphic after screening 75 accessions. The parameters used to characterize the loci were observed and expected heterozygosity, number of alleles, Shannon Index, and polymorphism information content (PIC). A total of 44 alleles were identified, with an average of 4.4 alleles per loci. The vast majority of loci were moderate to highly informative according to PIC and the Shannon Index. Conclusion: The new SSR markers have the potential to be informative tools for genetic diversity, allele mining, mapping and associative studies, and in the management and conservation of garlic collections.

Evaluation of plasma homocysteine level according to the C677T and A1298C polymorphism of the enzyme MTHRF in type 2 diabetic adults

Objective: To determine plasma homocysteine levels during fasting and after methionine overload, and to correlate homocysteinemia according to methylenetetrahydrofolate reductase (MTHFR) polymorphism in type 2 diabetic adults. Subjects and methods: The study included 50 type 2 diabetic adults (DM group) and 52 healthy subjects (Control group). Anthropometric data, and information on food intake, serum levels of vitamin B 12, folic acid and plasma homocysteine were obtained. The identification of C677T and A1298C polymorphisms was carried out in the MTHFR gene. Results: There was no significant difference in homocysteinemia between the two groups, and hyperhomocysteinemia during fasting occurred in 40% of the diabetic patients and in 23% of the controls. For the same polymorphism, there was not any significant difference in homocysteine between the groups. In the Control group, homocysteinemia was greater in those subjects with C677T and A1298C polymorphisms. Among diabetic subjects, those with the A1298C polymorphism had lower levels of homocysteine compared with individuals with C677T polymorphism. Conclusion: The MTHFR polymorphism (C677T and A1298C) resulted in different outcomes regarding homocysteinemia among individuals of each group (diabetic and control). These data suggest that metabolic factors inherent to diabetes influence homocysteine metabolism. Arq Bras Endocrinol Metab. 2012;56(7):429-34

Permanent Genetic Resources added to Molecular Ecology Resources Database 1 December 2011-31 January 2012

This article documents the addition of 473 microsatellite marker loci and 71 pairs of single-nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Barteria fistulosa, Bombus morio, Galaxias platei, Hematodinium perezi, Macrocentrus cingulum Brischke (a.k.a. M.abdominalis Fab., M.grandii Goidanich or M.gifuensis Ashmead), Micropogonias furnieri, Nerita melanotragus, Nilaparvata lugens Stal, Sciaenops ocellatus, Scomber scombrus, Spodoptera frugiperda and Turdus lherminieri. These loci were cross-tested on the following species: Barteria dewevrei, Barteria nigritana, Barteria solida, Cynoscion acoupa, Cynoscion jamaicensis, Cynoscion leiarchus, Cynoscion nebulosus, Cynoscion striatus, Cynoscion virescens, Macrodon ancylodon, Menticirrhus americanus, Nilaparvata muiri and Umbrina canosai. This article also documents the addition of 116 sequencing primer pairs for Dicentrarchus labrax.

Intron 4 polymorphism of the endothelial nitric oxide synthase (eNOS) gene is associated with decreased NO production in a mercury-exposed population

Nitric oxide (NO), produced by endothelial nitric oxide synthase (eNOS), is a potent vasodilator and plays a prominent role in regulating the cardiovascular system. Decreased basal NO release may predispose to cardiovascular diseases. Evidence suggests that the 27 nt repeat polymorphism of the intron 4 in the eNOS gene may regulate eNOS expression. On the other hand, some recent reports strongly suggest an association between methylmercury (MeHg) exposures and altered NO synthesis. In the present study, we investigate the contribution of the 27-pb tandem repeat polymorphism on nitric oxide production, which could enhance susceptibility to cardiovascular disease in the MeHg-exposed study population. Two-hundred-two participants (98 men and 104 women), all chronically exposed to MeHg through fish consumption were examined. Mean blood Hg concentration and nitrite plasma concentration were 50.5 +/- 35.4 mu g/L and 251.4 +/- 106.3 nM, respectively. Mean systolic and diastolic blood pressure were 120.1 +/- 19.4 mm Hg and 72.0 +/- 10.6 mm Hg, respectively. Mean body mass index was 24.5 +/- 4.3 kg/m(2) and the mean heart rate was 69.8 +/- 11.8 bpm. There were no significant differences in age, arterial blood pressure, body mass index or cardiac frequency between genotype groups (all P>0.05). However, we observed different nitrite concentrations in the genotypes groups, with lower nitrite levels for the 4a4a genotype carriers. Age, gender and the presence of intron 4 polymorphism contributed to nitrite reduction as a result of blood Hg concentration. Taken together, our results show that the 27 nt repeat polymorphism of the intron 4 in the eNOS gene increases susceptibility to cardiovascular diseases after MeHg exposure by modulating nitric oxide levels. (C) 2011 Elsevier B.V. All rights reserved.

Conformational polymorphism of the antidiabetic drug chlorpropamide

In this paper, the main features of Raman spectroscopy, one of the first choice methods in the study of polymorphism in pharmaceuticals, are presented taking chlorpropamide as a case of study. The antidiabetic drug chlorpropamide (1-[4-chlorobenzenesulphonyl]-3-propyl urea), which belongs to the sulfonylurea class, is known to exhibit, at least, six polymorphic phases. These forms are characterized not only by variations in their molecular packing but also in their molecular conformation. In this study, the polymorphism of chlorpropamide is discussed on the basis of Raman scattering measurements and quantum mechanical calculations. The main spectroscopic features that fingerprint the crystalline forms are correlated with the corresponding crystalline structures. Using a theoretical approach on the energy dependence of the conformers, simulated molecular torsion angles are plotted versus the formation energy, which provides a satisfactory agreement between the torsion angles at the energy minima and the experimental values observed in the different solid forms of chlorpropamide. Copyright (C) 2011 John Wiley & Sons, Ltd.

Functional Polymorphism Located in MMP-9 Gene Promoter Is Strongly Associated with Obesity

The adipose tissue expansion is accompanied by remodeling of extracellular matrix performed by matrix metalloproteinases (MMPs). Higher plasma and tissue MMP-9 levels are found in obese; therefore, we evaluated if the functional C-1562T polymorphism (rs3918242) located in promoter region of the MMP-9 gene is associated with obesity in women. We studied 112 lean and 114 obese women. Plasma MMP-9 and tissue inhibitor of MMP-9 (TIMP)-1 were measured using enzyme-linked immunosorbent assay. We found different genotype frequencies between lean and obese women (p = 0.008), prevailing T-allele in obese (2.3-fold). However, although obese women present higher levels of plasma MMP-9, lack of modulation by the polymorphism was found (all p > 0.05). Our findings suggest that C-1562T polymorphism may contribute to pathogenetic mechanisms involved in the development of obesity in women.

CYBA C242T polymorphism is associated with obesity and diabetes mellitus in Brazilian hypertensive patients

Diabet. Med. 29, e55e61 (2012) Abstract Aims The CYBA C242T polymorphism has been associated with cardiovascular phenotypes such as hypertension and atherosclerosis, but available data are conflicting. This report investigated the impact of this variant on hypertension and metabolic determinants of cardiovascular risk in a large Brazilian sample. Methods We cross-sectionally evaluated 1856 subjects (826 normotensive subjects and 1030 hypertensive patients) by clinical history, anthropometry, laboratory analysis and genotyping of the CYBA C242T polymorphism. Results Genotype frequencies in the whole population were consistent with the HardyWeinberg equilibrium and genotype distributions were not different between hypertensive and normotensive subjects. Hypertensive patients with the CC genotype presented lower fasting plasma glucose levels (5.9 +/- 0.1 vs. 6.2 +/- 0.1 mmol/l, P = 0.020) and waist circumference (94.5 +/- 0.6 vs. 96.3 +/- 0.6 cm, P = 0.028) than CT + TT ones. Similarly, the prevalence of diabetes mellitus and obesity was also lower in hypertensive patients carrying the CC genotype (16% vs. 21%, P = 0.041; 36% vs. 43%, P = 0.029, respectively). In addition, multiple and logistic regression analysis demonstrated that the CYBA C242T polymorphism was associated with glucose levels, waist circumference, obesity and diabetes mellitus in hypertensive patients independently of potential confounders. Conversely, in normotensive subjects, no significant difference in studied variables was detected between the genotype groups. Conclusions These data suggest that the T allele of the CYBA C242T polymorphism may be used as a marker for adverse metabolic features in Brazilian subjects with systemic hypertension.

Molecular characterization by amplified fragment length polymorphism and aflatoxin production of Aspergillus flavus isolated from freshly harvested peanut in Brazil

Brazil contributes substantially to the global peanut production, and the state of Sao Paulo is the largest producer in the country. Peanut crops can be contaminated by Aspergillus flavus strains producing aflatoxins, which are highly toxic and carcinogenic. Thus, the production of high-quality peanuts is crucial both for the commercial peanut industry and as a matter of public health. In this study, we used amplified fragment length polymorphism analysis (AFLP) to investigate the genetic variability among A. flavus strains isolated from fresh peanuts harvested in four different regions in the state of Sao Paulo, and to determine whether the molecular genetic profiles correlated with aflatoxin production or sclerotia formation. AFLP analysis generated 78 fragments ranging from 27 to 365 base pairs in length. Thirteen percent were not polymorphic. Genotyping identified twelve groups of A. flavus. On the basis of the polymorphisms identified, similarity between the isolates ranged from 37% to 100%. Of all isolates collected, 91.7% produced aflatoxins and 83.9% produced small sclerotia. Statistical analysis failed to suggest any relationship between the presence of sclerotia and mean levels of aflatoxins B-1 and B-2. Furthermore, a dendrogram based on AFLP data revealed substantial genetic variability among the A. flavus strains, but showed no correlation between dendrogram groups separated by molecular genetic features and production of aflatoxins B-1 or B-2 or the formation of sclerotia.

Microsatellite loci for the carpenter bee Xylocopa frontalis (Apidae, Xylocopini)

In the present study, a microsatellite-enriched genomic library was constructed and primers for 14 microsatellite loci were designed for Xylocopa frontalis. Twenty unrelated individuals were screened. All loci were polymorphic and the number of alleles per locus ranged from 6 to 17 (x = 10.43). Observed (H-o) and expected (H-e) heterozygosities ranged from 0.350 to 0.950 and 0.674 to 0.898, respectively. All loci were in Hardy-Weinberg equilibrium, except one. The microsatellite loci described in this study will contribute towards general biology studies of X. frontalis, intranidal genetic relationships and nest management for the pollination of passion fruit.