We investigated the possible additional value of body plethysmographic measures (specific resistance, residual volume-total lung capacity ratio [RV/TLC]) compared with spirometric measures forced expiratory volume in 1 second (FEV <sub>1</sub> ), forced vital capacity (FVC), FEV <sub>1</sub> /FVC, forced expiratory flow at 25% to 75% of forced vital capacity (FEF <sub>25-75</sub> ), and fraction of exhaled nitric oxide (FeNO) for assessment of asthma control.
We conducted a retrospective analysis of the effects of ADRB2 haplotypes at position 16 (Gly/Arg) and 27(Gln/Glu) in 449 patients with a physician diagnosis of asthma who were responsive to methacholine (ie, provocation concentration that caused a decrease in forced expiratory volume in 1 second [FEV(1)] of 20% [PC(20)], <8 mg/mL).
Although further studies for the non-synonymous Asp723Asn variation are needed, our findings suggest that DCBLD2 could be related to FEV(1)-related phenotypes in asthmatics.
Asthmatics were categorized into AERD <15% decreases in forced expiratory volume in one second (FEV(1)), and/or naso-ocular reactions after oral aspirin challenge (n=170) and aspirin-tolerant asthma (ATA, n=268).In all, 11 SNPs were genotyped.
Using phenotypic and GWAS genotype data available through the NHLBI-funded Single-nucleotide polymorphism Health association-Asthma Resource Project, we analyzed differences in FEV(1) in response to inhaled corticosteroids in 418 white subjects with asthma.
Despite the need for further functional evaluations and replications, we conclude that DDR1 polymorphisms are not likely to contribute to predispositions of AERD, but may be potentially associated with FEV(1) decline by aspirin provocation in asthmatics.
To examine the associations between polymorphisms in candidate genes in the leukotriene pathway and outcomes in patients with asthma on montelukast for 4-8 weeks, we evaluated the changes in peak expiratory flow (PEF), forced expiratory volume in 1 s (FEV(1·0) ) and patients' subjective symptom before and after montelukast treatment.
In further multiple regression analysis, no genetic variants of GTF2H4 showed significant associations with FEV(1) decline by aspirin provocation in asthmatics (P > 0.05).
We performed an association analysis between improvement of lung function - assessed by measurement of the percentage of the predicted forced expiratory volume in 1 second (%predicted FEV(1)), the ratio between the FEV(1) and the forced vital capacity (FEV(1)/FVC) after 6 and 12 months of treatment, and asthma control after 12 months of treatment - and two polymorphisms, rs2146323 and rs833058, in the VEGFA gene.
We found variant rs12212740, an intronic SNP of ATG5, to be associated with asthma and forced expiratory volume in 1 second (FEV(1)) percent predicted in the French Canadian population and with FEV(1) in an American Caucasian cohort.
Mean values of FEV(1) and FEF(25-75) (%predicted) were significantly lower in past-asthmatics than never-asthmatics without AHR, and the values in never-asthmatics with AHR were intermediate between never-asthmatics without AHR and past-asthmatics.
Asthmatics (n = 470) were categorized into AIA (20% or greater decreases in forced expiratory volume in 1 s [FEV(1)], or 15% to 19% decreases in FEV(1) with naso-ocular or cutaneous reactions) and aspirin-tolerant asthma (ATA).A total of 101 SNPs were genotyped. mRNA expression of the TBXAS1 gene by peripheral blood mononuclear cells and plasma thromboxane B2 (TXB2) concentrations were measured by reverse transcriptase (RT)-PCR and ELISA.
The first transcriptional phenotype (n = 21) had lower FEV(1)% predicted and higher asthma control questionnaire scores, exhaled nitric oxide, and sputum eosinophils.
We observed the most significant association with adult asthma at rs404860 in the major histocompatiblity complex region (P = 4.07 × 10(-23)), which is close to rs2070600, a SNP previously reported for association with FEV(1)/FVC in genome-wide association studies for lung function.
We hypothesized that a lower FEV(1) in these subjects is a potential marker of an increased susceptibility to obstructive lung disease such as asthma and COPD.
More interestingly, regression analysis of the decline of forced expiratory volume in one second (FEV(1)) by aspirin provocation revealed that 10 SNPs (P = 0.003-0.04) and four relevant haplotypes (P = 0.002-0.02) were significantly associated with the fall rate of FEV(1) by aspirin provocation, indicating that genetic polymorphisms of EMID2 could cause meaningful deficits in the upper and lower airways among AIA patients.
Of the identified SNPs, only a ten base pair insertion (CAATCTAGGC) in the 5'UTR region of exon 2 was significantly associated with lower FEV(1) (β = -14.63 SE = 6.241, P = 0.019) in Turkish children with asthma.
The expression quantitative trait loci revealed that five SNPs associated with asthma in CAMP/Illumina and one SNP associated with FEV(1) in CAMP are strongly correlated with SERPINE2 expression levels.
The "yin" haplotype (h0111101) was associated with 44% increased asthma risk (p=0.003) and reduced forced expiratory volume in 1 s (FEV(1)) growth from 10 to 18 years of age (-29.46 ml, p=0.07), whereas the "yang"(h1000010) haplotype was associated with 23% reduced asthma risk (p=0.13) and better FEV(1) growth (43.84 ml, p=0.01).
The increases in FEV(1) after inhalation of procaterol hydrochloride (Delta FEV(1) procaterol) or oxitropium bromide (Delta FEV(1) oxitropium), and after sequential inhalation of procaterol and oxitropium (total airway reversibility), were measured in 81 Japanese patients with moderate to severe asthma.
FEV(1) increased by 21.7% after 4 weeks of therapy in atopic asthmatics with the A/A genotype compared with an 8.6% increase in heterozygotes and a 5.8% increase in G/G homozygotes (p <0.01).
Asthma-related quantitative traits (total serum IgE, FEV(1), forced vital capacity, and FEV(1)/forced vital capacity) were also tested in identified candidate regions in 473 TENOR cases and 363 phenotyped controls without a history of asthma to analyze GWAS results further.