The mutation (p.Trp211Arg), which segregates with a disease phenotype characterized by either isolated IIP/IPF, or IPF associated with lung adenocarcinoma, is located in the carbohydrate recognition domain (CRD) of SP-A1 and involves a residue invariant throughout evolution, not only in SP-A1, but also in its close paralog SP-A2 and other CRD-containing proteins.
We identified a novel genome-wide significant signal of association with IPF susceptibility near A-kinase anchoring protein 13 (AKAP13; rs62025270, odds ratio [OR] 1·27 [95% CI 1·18-1·37], p=1·32 × 10<sup>-9</sup>) and confirmed previously reported signals, including in mucin 5B (MUC5B; rs35705950, OR 2·89 [2·56-3·26], p=1·12 × 10<sup>-66</sup>) and desmoplakin (DSP; rs2076295, OR 1·44 [1·35-1·54], p=7·81 × 10<sup>-28</sup>).
Furthermore, genetic variants of TOLLIP, MUC-5B, and other genes associated with a differential response to treatment and with the development and/or the prognosis of IPF are reported.
Secreted mucins (MUC2, MUC5AC, MUC5B, MUC6-8 and MUC19) are released to the extracellular medium and recent evidence has shown that a promoter polymorphism in the secreted mucin MUC5B is associated with IPF risk.
A common variant in mucin 5B predisposes to both familial and sporadic IPF and is present in the majority of cases, indicating sporadic IPF occurs in those with genetic predisposition.
Associations between 2 polymorphisms in TERT (rs2736100) and MUC5B (rs35705950) and IPF or non-IPF sporadic ILD were tested using 227 patients with ILD and 689 control subjects.
A promoter variant in MUC5B, rs35705950, was previously found to be strongly associated with the incidence of idiopathic pulmonary fibrosis (IPF) and also the overall survival (OS) of such patients.
Baseline bacterial burden predicted the rate of decline in lung volume and risk of death and associated independently with the rs35705950 polymorphism of the MUC5B mucin gene, a proven host susceptibility factor for IPF.
Furthermore, genetic variants of TOLLIP, MUC5B, and other genes are associated with a differential response to treatment and with the development and/or the prognosis of IPF.
The MUC5B promoter polymorphism was recently found to markedly elevate risk for IPF, though a particular association with NSIP has not been previously reported, nor has its contribution to disease risk previously been evaluated in the genome-wide context of all genetic variants.
Similarly, recent genetic studies have demonstrated strong and replicable associations between a common promoter polymorphism in the mucin 5B gene (MUC5B) and both IPF and the presence of abnormal imaging findings in the general population.
We genotyped the MUC5B promoter in the first 142 patients of the French national prospective cohort of IPF, in 981 French patients with SSc (346 ILD), 598 Italian patients with SSc (207 ILD), 1383 French controls and 494 Italian controls.
We found that the MUC5B promoter variant was associated with RA-ILD and more specifically associated with evidence of usual interstitial pneumonia on imaging.
The variation of G>T in the MUC5B promoter (rs35705950) has been associated with idiopathic pulmonary fibrosis (IPF) and familial interstitial pneumonia (FIP) in Caucasians, but no information is available regarding this variant in the Chinese population.
The strength of association was more remarkable in the Caucasian population than in the Asian population, and no homozygous TT genotype was detected in the Asian population in our study.Our study revealed strong association between the MUC5B promoter rs35705950 polymorphism and the risk of IPF.
To determine whether the MUC5B promoter polymorphism (rs35705950), previously reported to be associated with the development of pulmonary fibrosis, is associated with survival in IPF.