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08:58
En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Association between achalasia and nitric oxide synthase gene polymorphisms
Fermín Mearin1, María-Asunción García-González, Michael Strunk
1Institute of Functional and Motor Digestive Disorders, Centro Médico Teknon, Barcelona, Spain.
The American Journal of Gastroenterology
|July 20, 2006
Summary
Nitric oxide synthase (NOS) gene polymorphisms do not appear to influence achalasia susceptibility or its clinical course. Further research with larger patient cohorts is needed to confirm these findings for specific genotypes.
Area of Science:
- Genetics
- Gastroenterology
- Molecular Biology
Background:
- Nitric oxide synthase (NOS) absence was previously noted in the gastroesophageal junction of achalasia patients.
- NOS exists as three isoforms: neuronal (nNOS), endothelial (eNOS), and inducible (iNOS).
- Nitric oxide (NO) production may be modulated by NOS gene polymorphisms.
Purpose of the Study:
- To investigate the potential involvement of functional polymorphisms in nNOS, iNOS, and eNOS genes in achalasia susceptibility.
- To determine if specific NOS gene variants are associated with the risk of developing achalasia.
Main Methods:
- Genomic DNA was analyzed from 80 Spanish Caucasian achalasia patients and 144 healthy controls.
- Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods were used.
- Specific polymorphisms in eNOS (VNTR in intron 4), nNOS (microsatellite and Nla III RFLP in exon 29), and iNOS (nucleotide substitutions in exons 16 and 22) were genotyped.
Main Results:
- No significant differences in genotype or allele frequencies for nNOS, iNOS, or eNOS polymorphisms were observed between achalasia patients and controls.
- A trend towards higher frequency of homozygous iNOS22*A/A genotype (20% vs. 11%) and homozygous eNOS*4a allele carriers (6.2% vs. 1.4%) in achalasia patients did not reach statistical significance.
- No associations were found between genotype distributions and the epidemiological or clinical characteristics of achalasia.
Conclusions:
- Current data suggest that NOS gene polymorphisms are not a significant factor in the susceptibility or clinical progression of sporadic achalasia.
- Larger-scale studies are warranted to further investigate the observed tendencies for iNOS22*A/A and eNOS*4a4a genotypes.
- The role of NOS gene variations in achalasia requires additional investigation in diverse populations.
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