Targeted exome sequencing integrated with clinicopathological information reveals novel and rare mutations in atypical, suspected and unknown cases of Alport syndrome or proteinuria.

We applied customized targeted next-generation exome sequencing (NGS) to determine if mutations in genes associated with renal malformations, Alport syndrome (AS) or nephrotic syndrome are a potential cause of renal abnormalities in patients with equivocal or atypical presentation. We first sequenced 4,041 exons representing 292 kidney disease genes in a Caucasian woman with a history of congenital vesicoureteral reflux (VUR), recurrent urinary tract infections and hydronephrosis who presented with nephrotic range proteinuria at the age of 45. Her biopsy was remarkable for focal segmental glomerulosclerosis (FSGS), a potential complication of longstanding VUR.

Traditional and targeted exome sequencing reveals common, rare and novel functional deleterious variants in RET-signaling complex in a cohort of living US patients with urinary tract malformations.

Signaling by the glial cell line-derived neurotrophic factor (GDNF)-RET receptor tyrosine kinase and SPRY1, a RET repressor, is essential for early urinary tract development. Individual or a combination of GDNF, RET and SPRY1 mutant alleles in mice cause renal malformations reminiscent of congenital anomalies of the kidney or urinary tract (CAKUT) in humans and distinct from renal agenesis phenotype in complete GDNF or RET-null mice. We sequenced GDNF, SPRY1 and RET in 122 unrelated living CAKUT patients to discover deleterious mutations that cause CAKUT.

Expression profiles of podocytes exposed to high glucose reveal new insights into early diabetic glomerulopathy.

Podocyte injury has been suggested to have a pivotal role in the pathogenesis of diabetic glomerulopathy. To glean insights into molecular mechanisms underlying diabetic podocyte injury, we generated temporal global gene transcript profiles of podocytes exposed to high glucose for a time interval of 1 or 2 weeks using microarrays. A number of genes were altered at both 1 and 2 weeks of glucose exposure compared with controls grown under normal glucose.

A common exonic variant of interleukin21 confers susceptibility to atopic asthma.

Background: Interleukin (IL)-21, an IL-2 family multifunctional cytokine, is produced by activated CD4+ T cells and is known to potentially affect growth, survival and function of numerous immune cells. As IL-21 regulates IgE production, a key mediator of various allergic disorders and asthma, it is a prime candidate gene for studying atopic asthma.

Methods: In atopic asthma, analyses of four single nucleotide polymorphisms (SNP; C1455T, G1472T, C5250T and C8381T), a tetranucleotide microsatellite repeat (GAAT)(n) and their haplotypes were performed, and serum total IgE (TsIgE) was determined in ethnically matched unrelated patients (n = 255), unrelated controls (n = 245) and nuclear families (n = 140).

Genetic association of acidic mammalian chitinase with atopic asthma and serum total IgE levels.

Background: In view of the hygiene hypothesis and the involvement of acidic mammalian chitinase (CHIA) in the effector responses of IL-13 with asthma, CHIA (GeneID-27159) is a potential asthma candidate gene.

Objective: To investigate the association of CHIA polymorphisms with atopic asthma and serum total IgE levels.

Methods: Twenty-one single nucleotide polymorphisms were identified by sequencing DNA of 60 individuals.

Inducible nitric oxide synthase (iNOS): role in asthma pathogenesis.

Asthma is one of the most common chronic inflammatory disorder of the airways of the lungs, affecting more than 300 million people all over the world. Nitric oxide (NO) is endogenously produced in mammalian airways by nitric oxide synthase (NOS) and is known to regulate many aspects of human asthma, including the modulation of airway and vascular smooth muscle tone and the inflammation. Asthmatic patients show an increased expression of inducible nitric oxide synthase (iNOS) in airway epithelial cells and an increased level of NO in exhaled air.