Analysis of the Gut Mycobiome in Adult Patients with Type 1 and Type 2 Diabetes Using Next-Generation Sequencing (NGS) with Increased Sensitivity—Pilot Study

The studies on microbiome in the human digestive tract indicate that fungi could also be one of the external factors affecting development of diabetes. The aim of this study was to evaluate the quantitative and qualitative mycobiome composition in the colon of the adults with type 1 (T1D), n = 26 and type 2 (T2D) diabetes, n = 24 compared to the control group, n = 26. The gut mycobiome was characterized in the stool samples using the analysis of the whole internal transcribed spacer (ITS) region of the fungal rDNA gene cluster by next-generation sequencing (NGS) with increased sensitivity. At the L2 (phylum) level, Basidiomycota fungi were predominant in all 3 study groups. Group T1D presented significantly lower number of Ascomycota compared to the T2D group, and at the L6 (genus) level, the T1D group presented significantly lower number of Saccharomyces genus compared to control and T2D groups. In the T1D group, a significant positive correlation between total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels and fungi of the genus Saccharomyces, and in the T2D group, a negative correlation between the total cholesterol level and Malassezia genus was found. The obtained results seem to be a good foundation to extend the analysis of the relationship between individual genera and species of fungi and the parameters determining the metabolism of carbohydrates and lipids in the human body.

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Novel SCNN1A Gene Splicing-site Mutation Causing Autosomal Recessive Pseudohypoaldosteronism type 1 (PHA1) in two Italian Patients Belonging to the Same Small Town

10.21203/rs.3.rs-432720/v1 ◽

2021 ◽

Author(s):

Gregorio Serra ◽

Vincenzo Antona ◽

Maria Michela D’Alessandro ◽

Maria Cristina Maggio ◽

Vincenzo Verde ◽

...

Keyword(s):

Metabolic Acidosis ◽

Next Generation Sequencing ◽

Family History ◽

Gene Mutation ◽

Small Town ◽

Next Generation ◽

Next Generation Sequencing Ngs ◽

Generation Sequencing ◽

Pseudohypoaldosteronism Type

Abstract IntroductionPseudohypoaldosteronism type 1 (PHA1) is a rare genetic disease due to the peripheral resistance to aldosterone. Its clinical spectrum includes neonatal salt loss syndrome with hyponatremia and hypochloraemia, hyperkalemia, metabolic acidosis and increased plasmatic levels of aldosterone. Two genetically distinct forms of disease, renal and systemic, have been described, showing a wide clinical expressivity. Mutations in the genes encoding for the subunits of the epithelial sodium channels (ENaC) are responsible for generalized PHA1. Patients’ presentationWe hereby report on two Italian patients with generalized PHA1, coming from the same small town in the center of Sicily. The first patient is a male child, born from the first pregnancy of healthy consanguineous Sicilian parents. A novel SCNN1A (sodium channel epithelial subunit alpha) gene mutation, inherited from both heterozygous parents, was identified by next generation sequencing (NGS) in the homozygous child (and later, also in the heterozygous maternal aunt). A more detailed family history disclosed a possible related twenty-year-old girl, belonging to the same Sicilian small town, with referred neonatal salt loss syndrome associated to hyperkalemia, and subsequent normal growth and neurodevelopment. This second patient had a PHA1 clinical diagnosis when she was about one year old. The genetic investigation was, then, extended to her and to her family, revealing the same mutation in the homozygous girl and in the heterozygous parents.ConclusionsThe neonatologist should consider PHA1 diagnosis in newborns showing hyponatremia, hyperkalemia and metabolic acidosis, after the exclusion of a salting-loss form of adrenogenital syndrome. The increased plasmatic levels of aldosterone and aldosterone/renin ratio, associated to a poor response to steroid administration, confirmed the diagnosis in the first present patient. An accurate family history may be decisive to identify the clinical picture. A multidisciplinary approach and close follow-up evaluations are requested, in view of optimal management, adequate growth and development of patients. Next generation sequencing (NGS) techniques allowed the identification of the SCNN1A gene mutation either in both patients or in other heterozygous family members, enabling also primary prevention of disease. Our report may broaden the knowledge of the genetic and molecular bases of PHA1, improving its clinical characterization and providing useful indications for the treatment of patients. Clinical approach must be personalized, also in relation to long-term survival and potential multiorgan complications.

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New Genotypes and Phenotypes in Patients with 3 Subtypes of Waardenburg Syndrome Identified by Diagnostic Next-Generation Sequencing

Neural Plasticity ◽

10.1155/2019/7143458 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Wu Li ◽

Lingyun Mei ◽

Hongsheng Chen ◽

Xinzhang Cai ◽

Yalan Liu ◽

...

Keyword(s):

Next Generation Sequencing ◽

De Novo ◽

Waardenburg Syndrome ◽

Next Generation ◽

Single Nucleotide Variants ◽

Number Variation ◽

First Time ◽

Generation Sequencing

Background. Waardenburg syndrome (WS) is one of the most common forms of syndromic deafness with heterogeneity of loci and alleles and variable expressivity of clinical features. Methods. The technology of single-nucleotide variants (SNV) and copy number variation (CNV) detection was developed to investigate the genotype spectrum of WS in a Chinese population. Results. Ninety WS patients and 24 additional family members were recruited for the study. Fourteen mutations had not been previously reported, including c.808C>G, c.117C>A, c.152T>G, c.803G>T, c.793-3T >G, and c.801delT on PAX3; c.642_650delAAG on MITF; c.122G>T and c.127C>T on SOX10; c.230C>G and c.365C>T on SNAI2; and c.481A>G, c.1018C>G, and c.1015C>T on EDNRB. Three CNVs were de novo and first reported in our study. Five EDNRB variants were associated with WS type 1 in the heterozygous state for the first time, with a detection rate of 22.2%. Freckles occur only in WS type 2. Yellow hair, amblyopia, congenital ptosis, narrow palpebral fissures, and pigmentation spots are rare and unique symptoms in WS patients from China. Conclusions. EDNRB should be considered as another prevalent pathogenic gene in WS type 1. Our study expanded the genotype and phenotype spectrum of WS, and diagnostic next-generation sequencing is promising for WS.

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Determination ofRETSequence Variation in an MEN2 Unaffected Cohort Using Multiple-Sample Pooling and Next-Generation Sequencing

Journal of Thyroid Research ◽

10.1155/2012/318232 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

R. L. Margraf ◽

J. D. Durtschi ◽

J. E. Stephens ◽

M. Perez ◽

K. V. Voelkerding

Keyword(s):

Next Generation Sequencing ◽

Sequence Variation ◽

High Resolution Melting ◽

Next Generation ◽

Sample Pooling ◽

Melting Analysis ◽

Multiple Sample ◽

Next Generation Sequencing Ngs ◽

Generation Sequencing

Multisample, nonindexed pooling combined with next-generation sequencing (NGS) was used to discoverRETproto-oncogene sequence variation within a cohort known to be unaffected by multiple endocrine neoplasia type 2 (MEN2). DNA samples (113 Caucasians, 23 persons of other ethnicities) were amplified forRETintron 9 to intron 16 and then divided into 5 pools of <30 samples each before library prep and NGS. Two controls were included in this study, a single sample and a pool of 50 samples that had been previously sequenced by the same NGS methods. All 59 variants previously detected in the 50-pool control were present. Of the 61 variants detected in the unaffected cohort, 20 variants were novel changes. Several variants were validated by high-resolution melting analysis and Sanger sequencing, and their allelic frequencies correlated well with those determined by NGS. The results from this unaffected cohort will be added to theRETMEN2 database.

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Novel SCNN1A gene splicing-site mutation causing autosomal recessive pseudohypoaldosteronism type 1 (PHA1) in two Italian patients belonging to the same small town

Italian Journal of Pediatrics ◽

10.1186/s13052-021-01080-x ◽

2021 ◽

Vol 47 (1) ◽

Author(s):

Gregorio Serra ◽

Vincenzo Antona ◽

Maria Michela D’Alessandro ◽

Maria Cristina Maggio ◽

Vincenzo Verde ◽

...

Keyword(s):

Metabolic Acidosis ◽

Next Generation Sequencing ◽

Family History ◽

Gene Mutation ◽

Small Town ◽

Next Generation ◽

Next Generation Sequencing Ngs ◽

Generation Sequencing ◽

Pseudohypoaldosteronism Type

Abstract Introduction Pseudohypoaldosteronism type 1 (PHA1) is a rare genetic disease due to the peripheral resistance to aldosterone. Its clinical spectrum includes neonatal salt loss syndrome with hyponatremia and hypochloraemia, hyperkalemia, metabolic acidosis and increased plasmatic levels of aldosterone. Two genetically distinct forms of disease, renal and systemic, have been described, showing a wide clinical expressivity. Mutations in the genes encoding for the subunits of the epithelial sodium channels (ENaC) are responsible for generalized PHA1. Patients’ presentation We hereby report on two Italian patients with generalized PHA1, coming from the same small town in the center of Sicily. The first patient is a male child, born from the first pregnancy of healthy consanguineous Sicilian parents. A novel SCNN1A (sodium channel epithelial subunit alpha) gene mutation, inherited from both heterozygous parents, was identified by next generation sequencing (NGS) in the homozygous child (and later, also in the heterozygous maternal aunt). A more detailed family history disclosed a possible related twenty-year-old girl, belonging to the same Sicilian small town, with referred neonatal salt loss syndrome associated to hyperkalemia, and subsequent normal growth and neurodevelopment. This second patient had a PHA1 clinical diagnosis when she was about 1 year old. The genetic investigation was, then, extended to her and to her family, revealing the same mutation in the homozygous girl and in the heterozygous parents. Conclusions The neonatologist should consider PHA1 diagnosis in newborns showing hyponatremia, hyperkalemia and metabolic acidosis, after the exclusion of a salting-loss form of adrenogenital syndrome. The increased plasmatic levels of aldosterone and aldosterone/renin ratio, associated to a poor response to steroid administration, confirmed the diagnosis in the first present patient. An accurate family history may be decisive to identify the clinical picture. A multidisciplinary approach and close follow-up evaluations are requested, in view of optimal management, adequate growth and development of patients. Next generation sequencing (NGS) techniques allowed the identification of the SCNN1A gene mutation either in both patients or in other heterozygous family members, enabling also primary prevention of disease. Our report may broaden the knowledge of the genetic and molecular bases of PHA1, improving its clinical characterization and providing useful indications for the treatment of patients. Clinical approach must be personalized, also in relation to long-term survival and potential multiorgan complications.

Download Full-text