Open reading frame expressed sequences tags (ORESTES) differ from conventional ESTs by providing sequence data from the central protein coding portion of transcripts. We generated a total of 696,745 ORESTES sequences from 24 human tissues and used a subset of the data that correspond to a set of 15,095 full-length mRNAs as a means of assessing the efficiency of the strategy and its potential contribution to the definition of the human transcriptome. We estimate that ORESTES sampled over 80% of all highly and moderately expressed, and between 40% and 50% of rarely expressed, human genes. In our most thoroughly sequenced tissue, the breast, the 130,000 ORESTES generated are derived from transcripts from an estimated 70% of all genes expressed in that tissue, with an equally efficient representation of both highly and poorly expressed genes. In this respect, we find that the capacity of the ORESTES strategy both for gene discovery and shotgun transcript sequence generation significantly exceeds that of conventional ESTs. The distribution of ORESTES is such that many human transcripts are now represented by a scaffold of partial sequences distributed along the length of each gene product. The experimental joining of the scaffold components, by reverse transcription–PCR, represents a direct route to transcript finishing that may represent a useful alternative to full-length cDNA cloning.
Mutations linked to familial hypokalaemic periodic paralysis in the calcium channel alpha1 subunit gene (Cav1.1) are not associated with thyrotoxic hypokalaemic periodic paralysis. However, polymorphisms in nucleotides 1551 and 1564 in the exon 11 were found in patients with familial hypokalaemic periodic paralysis and thyrotoxic hypokalaemic periodic paralysis in higher frequency than in controls. The polymorphisms identified within the Cav1.1 gene are associated with thyrotoxic hypokalaemic periodic paralysis and represent a novel finding.
Background: Type 2 diabetes mellitus (T2DM) is a genetically heterogeneous disease, hepatocyte nuclear factor-1 homeobox A (HNF1A) single-nucleotide polymorphisms (SNPs) playing a minor role in its pathogenesis. HNF1A is a frequent cause of monogenic diabetes, albeit with early-onset. Some uncommon subgroups like late-onset autosomal dominant diabetes mellitus (LOADDM) may present peculiar inheritance patterns with a stronger familial component. This study aims to investigate the relationship of HNF1A SNPs with cardiovascular risk factors in this group, as well as to characterize them in contrast with classical T2DM (CT2DM).
Germline mutations in codon 918 of exon 16 of the RET gene (M918T) are classically associated with multiple endocrine neoplasia type 2B (MEN 2B) with highly aggressive medullary thyroid cancer (MTC), pheochromocytoma and a unique phenotype. The objectives of this study are to describe the rare M918V RET mutation discovered in 8 MTC kindreds from Brazil lacking the MEN 2B phenotype classically observed in M918T patients and to investigate the presence of a founder effect for this germline mutation. Eight apparently sporadic MTC cases were diagnosed with the germline M918V RET mutation. Subsequently, their relatives underwent clinical and genetic assessment (n = 113), and M918V was found in 42 of them. Until today, 20/50 M918V carriers underwent thyroidectomy and all presented MTC/C-cell hyperplasia; the remainder carriers are on clinical follow-up. None of the M918V carriers presented clinical features of MEN 2B. Their clinical presentation was heterogeneous, and the age at tumor diagnosis ranged from 24 to 59 years. Lymph node metastases were present in 12/20 patients, and presumable distant metastases in 2/20; in contrast, we observed a carrier of up to 87 years of age without evidence of MTC. Ethnographic fieldwork and haplotype analyses suggested that the founder mutation first settled in that area fifteen generations ago and originated from Portugal. Our study is the first to demonstrate the RET M918V mutation co-segregating in 8 familial MTC kindreds with validated evidence of a founder effect. We suggest that M918V MTC should be clinically considered an American Thyroid Association (ATA) moderate-risk category.
Desenvolvemos método semi-automatizado em placa para a determinação de iodo urinário; utilizamos, primeiramente, a digestão das amostras de urina com persulfato de amônio e, a seguir, estimamos a quantidade de iodo pela redução do sulfato cérico amoniacal. O método foi validado no inquérito nacional de monitoração da deficiência de iodo, realizado em 1994, que empregou um sistema de amostragem mista da população brasileira e analisou a iodúria em 16.803 amostras de urina de escolares obtidas por coleta casual. Em 401 municípios estudados encontramos 4 com deficiência de iodo de grau moderado (Almas, Arraias e Paraná, em Tocantins, e Cocos, na Bahia) e 116 de grau leve. Desta forma, este estudo mostrou a presença de regiões com deficiência de iodo em 1994, a despeito do programa de iodação do sal. Dados recentes de outros autores, com número menor de municípios, indicam excesso de ingestão de iodo. Assim, num país de dimensões continentais e heterogêneo como o Brasil, é necessária a realização de avaliações periódicas de amplitude nacional para a verificação da ingestão de iodo da população. O método apresentado neste estudo apresenta as características de simplicidade e eficiência necessários para este tipo de estudo populacional.
Next-generation sequencing (NGS) has enriched the understanding of the human genome. However, homologous or repetitive sequences shared among genes frequently produce dubious alignments and can puzzle NGS mutation analysis, especially for paralogous potassium channels. Potassium inward rectifier (Kir) channels are important to establish the resting membrane potential and regulating the muscle excitability. Mutations in Kir channels cause disorders affecting the heart and skeletal muscle, such as arrhythmia and periodic paralysis. Recently, a susceptibility muscle channelopathy-thyrotoxic periodic paralysis (TPP)-has been related to Kir2.6 channel (KCNJ18 gene). Due to their high nucleotide sequence homology, variants found in the potassium channels Kir2.6 and Kir2.5 have been mistakenly attributable to Kir2.2 polymorphisms or mutations. We aimed at elucidating nucleotide misalignments by performing realignment of whole exome sequencing (WES) and whole genome sequencing (WGS) reads to specific Kir2.2, Kir2.5, and Kir2.6 cDNA sequences using BWA-MEM/GATK pipeline. WES/WGS reads correctly aligned 26.9/43.2, 37.6/31.0, and 35.4/25.8 % to Kir2.2, Kir2.5, and Kir2.6, respectively. Realignment was able to reduce over 94 % of misalignments. No putative mutations of Kir2.6 were identified for the three TPP patients included in the cohort of 36 healthy controls using either WES or WGS. We also distinguished sequences for a single Kir2.2, a single Kir2.5 sequence, and two Kir2.6 isoforms, which haplotypes were named RRAI and QHEV, based on changes at 39, 40, 56, and 249 residues. Electrophysiology records on both Kir2.6_RRAI and _QHEV showed typical rectifying currents. In our study, the reduction of misalignments allowed the elucidation of paralogous gene sequences and two distinct Kir2.6 haplotypes, and pointed the need for checking the frequency of these polymorphisms in other populations with different genetic background.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.