Vanessa Santos Sotomaior

Association between Vitamin D Receptor Gene Polymorphisms and Susceptibility to Chronic Kidney Disease and Periodontitis

Background/Aims: Chronic kidney disease (CKD) and periodontitis (PD) are serious public-health concerns. Vitamin D is a fat-soluble steroid hormone that interacts with its nuclear receptor (VDR) to regulate a variety of biological processes, such as bone metabolism, immune response modulation and transcription of several genes involved in CKD and PD disease mechanisms. The aim of this work was to investigate the association between polymorphisms in the VDR gene and end-stage renal disease (ESRD) and PD. Methods: 222 subjects with and without ESRD (in hemodialysis) were divided into groups with and without PD. Polymorphisms TaqI and BsmI in the VDR gene were analyzed by PCR restriction fragment length polymorphism. The significance of differences in allele, genotype and haplotype frequencies between groups was assessed by the χ2 test (p value <0.05) and odds ratio (OR). Results: Allele G was associated with protection against ESRD: groups without versus with ESRD (GG) × (GA+AA): OR = 2.5, 95% CI = 1.4–4.6, p = 0.00; (G × A): OR = 1.5, 95% CI = 1.0–2.3, p = 0.02; (TG + CG) × (TA + CA): OR = 1.5, 95% CI = 1.0–2.3, p = 0.02. No association was observed between the study polymorphisms and susceptibility to or protection against PD. Conclusion: Allele G of the VDR BsmI polymorphism was associated with protection against ESRD.

Huntington disease: DNA analysis in brazilian population

Huntington disease (HD) is associated with expansions of a CAG trinucleotide repeat in the HD gene. Accurate measurement of a specific CAG repeat sequence in the HD gene in 92 Brazilian controls without HD, 44 Brazilian subjects with clinical findings suggestive of HD and 40 individuals from 6 putative HD families, showed a range from 7 to 33 repeats in normal subjects and 39 to 88 repeats in affected subjects. A trend between early age at onset of first symptoms and increasing number of repeats was seen. Major increase of repeat size through paternal inheritance than through maternal inheritance was observed. Data generated from this study may have significant implications for the etiology, knowledge of the incidence, diagnosis, prognosis, genetic counseling and treatment of HD Brazilian patients.

Analysis of Polymorphisms in the Lactotransferrin Gene Promoter and Dental Caries

Regarding host aspects, there has been strong evidence for a genetic component in the etiology of caries. The salivary protein lactotransferrin (LTF) exhibits antibacterial activity, but there is no study investigating the association of polymorphisms in the promoter region of LTF gene with caries. The objective of this study was firstly to search the promoter region of the human LTF gene for variations and, if existent, to investigate the association of the identified polymorphisms with dental caries in 12-year-old students. From 687 unrelated, 12-year-old, both sex students, 50 individuals were selected and divided into two groups of extreme phenotypes according to caries experience: 25 students without (DMFT = 0) and 25 with caries experience (DMFT ≥ 4). The selection of individuals with extreme phenotypes augments the chances to find gene variations which could be associated with such phenotypes. LTF gene-putative promoter region (+39 to −1143) of the selected 50 individuals was analyzed by high-resolution melting technique. Fifteen students, 8 without (DMFT = 0) and 7 with caries experience (mean DMFT = 6.28), presented deviations of the pattern curve suggestive of gene variations and were sequenced. However, no polymorphisms were identified in the putative promoter region of the LTF gene.

Transplantation of SNAP-treated adipose tissue-derived stem cells improves cardiac function and induces neovascularization after myocardium infarct in rats

Stem cell therapy has been considered a promise for damaged myocardial tissue. We have previously shown that S-nitroso-N-acetyl-D,L-penicillamine (SNAP) increases the expression of several muscular markers and VEGF in mesenchymal stem cells, indicating that transplantation of SNAP-treated cells could provide better functional outcomes. Here, we transplanted SNAP-treated adipose tissue-derived stem cells (ADSCs) in rat infarcted myocardium. After 30days, we observed a significant improvement of the ejection fraction in rats that received SNAP-treated ADSCs, compared with those that received untreated cells (p=0.008). Immunohistochemical reactions showed an increased expression of troponin T-C and von Willebrand factor, and organized vascular units in the infarcted area of tissue transplanted with treated ADSCs. SNAP exposure induced intracellular S-nitrosation, a decreased GSH/GSSG ratio, but did not increase cGMP levels. Collectively, these results indicate that SNAP alters the redox environment of ADSCs, possibly associated with a pre-differentiation state, which may improve cardiac function after transplantation.

A 1.5Mb terminal deletion of 12p associated with autism spectrum disorder.

We report a patient with a terminal 12p deletion associated with autism spectrum disorder (ASD). This 12p13.33 deletion is 1.5Mb in size and encompasses 13 genes (B4GALNT3, CCDC77, ERC1, FBXL14, IQSEC3, KDM5A, LINC00942, LOC574538, NINJ2, RAD52, SLC6A12, SLC6A13 and WNK1). All previous cases reported with partial monosomy of 12p13.33 are associated with neurodevelopmental delay, and we suggest that ERC1, which encodes a regulator of neurotransmitter release, is the best gene candidate contributing to this phenotype as well as to the ASD of our patient.

Chromosome 19p13.3 deletion in a child with Peutz-Jeghers syndrome, congenital heart defect, high myopia, learning difficulties and dysmorphic features: clinical and molecular characterization of a new contiguous gene syndrome

The Peutz-Jeghers syndrome (PJS) is an autosomal-dominant hamartomatous polyposis syndrome characterized by mucocutaneous pigmentation, gastrointestinal polyps and the increased risk of multiple cancers. The causative point mutation in the STK11 gene of most patients accounts for about 30% of the cases of partial and complete gene deletion. This is a report on a girl with PJS features, learning difficulties, dysmorphic features and cardiac malformation, bearing a de novo 1.1 Mb deletion at 19p13.3. This deletion encompasses at least 47 genes, including STK11. This is the first report on 19p13.3 deletion associated with a PJS phenotype, as well as other atypical manifestations, thereby implying a new contiguous gene syndrome.

Mosaic partial trisomy 19p12-q13.11 due to a small supernumerary marker chromosome: A locus associated with Asperger syndrome?†

In the neurodevelopmentally impaired population the frequency of small supernumerary marker chromosomes (sSMC) is about 0.3%. To find the origin of a sSMC in a 4‐year‐old boy with Asperger syndrome (AS) a microarray‐based comparative genomic hybridization (aCGH), using a 135K‐feature whole‐genome microarray, and Metaphase FISH analysis, was performed. The sSMC was characterized as being composed of 18.4 Mb from 19p12q13.11. Based on the size and genic content, it is expected that the partial trisomy detected is responsible for the characteristics observed in the patient. In that case it could be an indication of a novel locus associated with AS.

What can be done when asymptomatic patients discover they have Brugada syndrome? A case report of Brugada syndrome

Brugada syndrome is an inherited cardiac disorder associated with a specific electrocardiographic pattern, involving ST segment elevation in leads V1 to V3. When not spontaneously terminated, it can lead to ventricular fibrillation and sudden death. We present a case report of a young male whose brother suffered a sudden cardiac arrest while playing soccer. A novel mutation c.2678G>A was detected on the gene SCN5A through molecular diagnosis. The mutation was shown to be present in the individual, his daughter and his other brother. For patients with previous ventricular fibrillation and/or syncope, implantable cardiac device (ICD) is recommended. However, how can patients without symptoms but with a clear diagnosis prevent cardiac arrest?

STR data for 15 autosomal STR markers from Paraná (Southern Brazil)

Allelic frequencies for 15 STR autosomal loci, using AmpFℓSTR® Identifiler™, forensic, and statistical parameters were calculated. All loci reached the Hardy–Weinberg equilibrium. The combined power of discrimination and mean power of exclusion were 0.999999999999999999 and 0.9999993, respectively. The MDS plot and NJ tree analysis, generated by FST matrix, corroborated the notion of the origins of the Paraná population as mainly European-derived. The combination of these 15 STR loci represents a powerful strategy for individual identification and parentage analyses for the Paraná population.

Congenital bilateral absence of the vas deferens as an atypical form of cystic fibrosis: reproductive implications and genetic counseling

Congenital bilateral absence of the vas deferens (CBAVD) is found in 1% to 2% of males with infertility and is present in 6% of obstructive azoospermia cases. Nearly 95% of men with cystic fibrosis (CF, an autosomal recessive disorder) have CBAVD. There are genetic links between CBAVD and CF. Some mutations in the gene encoding cystic fibrosis transmembrane conductance regulator (CFTR) can lead to CBAVD as a monosymptomatic form of CF. With the use of assisted reproductive techniques (ART), especially testicular or epididymal sperm aspiration, intracytoplasmic sperm injection, and in vitro fertilization, it is possible that men with CBAVD can produce offspring. Therefore, genetic counseling should be offered to couples undergoing ART to discuss the probability of having offspring that carry CFTR gene mutations. The aim of this review was to present the main cause of CBAVD, to call attention to its implications for assisted reproduction, and to show the importance of genetic counseling for couples where men have CBAVD, as they can have offspring with a lethal disease.