Dataset Information

Alpha-1 Antitrypsin PiMZ Genotype Is Associated with Chronic Obstructive Pulmonary Disease in Two Racial Groups.

ABSTRACT:

Rationale

Alpha-1 antitrypsin deficiency, caused primarily by homozygosity for the Z allele of the SERPINA1 gene, is a well-established genetic cause of chronic obstructive pulmonary disease (COPD). Whether the heterozygous PiMZ genotype for alpha-1 antitrypsin confers increased risk for COPD has been debated.

Objectives

We analyzed 8,271 subjects in the Genetic Epidemiology of COPD (COPDGene) Study, hypothesizing that PiMZ would independently associate with COPD and COPD-related phenotypes.

Methods

The COPDGene Study comprises a multiethnic, cross-sectional, observational cohort of non-Hispanic white and African American current and former smokers with at least 10 pack-years of smoking who were enrolled for detailed clinical and genetic studies of COPD and COPD-related traits. We performed multivariate logistic regression analysis for moderate to severe COPD and assessed Pi genotype with other relevant covariates in models stratified by race. We analyzed quantitative characteristics on the basis of volumetric computed tomography with generalized linear models controlling for genotype, scanner type, and similar covariates.

Results

White PiMZ COPDGene subjects had significantly lower lung function, FEV₁ percent predicted (68?±?28 vs. 75?±?27; P?=?0.0005), and FEV₁/FVC ratio (0.59?±?0.18 vs. 0.63?±?0.17; P?=?0.0008), as well as more radiographic emphysema (P?=?0.001), than subjects without alpha-1 antitrypsin Z risk alleles. Similarly, African American PiMZ subjects had lower lung function, FEV₁ percent predicted (65?±?33 vs. 84?±?25; P?=?0.009) and FEV₁/FVC (0.61?±?0.21 vs. 0.71?±?0.15; P?=?0.03).

Conclusions

In the COPDGene Study, we demonstrate that PiMZ heterozygous individuals who smoke are at increased risk for COPD and obstructive lung function impairment compared with Z-allele noncarriers, regardless of race. Although severe alpha-1 antitrypsin deficiency is uncommon in African Americans, our study adds further support for initial targeted detection of all subjects with COPD for alpha-1 antitrypsin deficiency, including African Americans. Clinical trial registered with www.clinicaltrials.gov (NCT00608784).

SUBMITTER: Foreman MG

PROVIDER: S-EPMC5566271 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Publications

Alpha-1 Antitrypsin PiMZ Genotype Is Associated with Chronic Obstructive Pulmonary Disease in Two Racial Groups.

Foreman Marilyn G MG Wilson Carla C DeMeo Dawn L DL Hersh Craig P CP Beaty Terri H TH Cho Michael H MH Ziniti John J Curran-Everett Douglas D Criner Gerard G Hokanson John E JE Brantly Mark M Rouhani Farshid N FN Sandhaus Robert A RA Crapo James D JD Silverman Edwin K EK

Annals of the American Thoracic Society 20170801 8

<h4>Rationale</h4>Alpha-1 antitrypsin deficiency, caused primarily by homozygosity for the Z allele of the SERPINA1 gene, is a well-established genetic cause of chronic obstructive pulmonary disease (COPD). Whether the heterozygous PiMZ genotype for alpha-1 antitrypsin confers increased risk for COPD has been debated.<h4>Objectives</h4>We analyzed 8,271 subjects in the Genetic Epidemiology of COPD (COPDGene) Study, hypothesizing that PiMZ would independently associate with COPD and COPD-related ...[more]

PMID: 28380308

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Dataset Information

Alpha-1 Antitrypsin PiMZ Genotype Is Associated with Chronic Obstructive Pulmonary Disease in Two Racial Groups.

Rationale

Objectives

Methods

Results

Conclusions

Publications

Alpha-1 Antitrypsin PiMZ Genotype Is Associated with Chronic Obstructive Pulmonary Disease in Two Racial Groups.

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