Clinical Chemistry
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 54: 1331-1338, 2008. First published May 29, 2008; 10.1373/clinchem.2007.102798
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Supplement Data
Right arrow All Versions of this Article:
clinchem.2007.102798v1
54/8/1331    most recent
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Zorzetto, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zorzetto, M.
Related Collections
Right arrow Molecular Diagnostics and Genetics
(Clinical Chemistry. 2008;54:1331-1338.)
© 2008 American Association for Clinical Chemistry, Inc.

Molecular Diagnostics and Genetics

SERPINA1 Gene Variants in Individuals from the General Population with Reduced {alpha}1-Antitrypsin Concentrations

Michele Zorzetto1, Erich Russi2, Oliver Senn2,3, Medea Imboden3,4, Ilaria Ferrarotti1, Carmine Tinelli1, Ilaria Campo1, Stefania Ottaviani1, Roberta Scabini1, Arnold von Eckardstein4, Wolfgang Berger5, Otto Brändli6, Thierry Rochat7, Maurizio Luisetti1, Nicole Probst-Hensch3,a the SAPALDIA Team

1 Center for Diagnosis of Severe Alpha1-antitrypsin Deficiency, Laboratory of Biochemistry and Genetics, Institute for Respiratory Disease and Unit of Statistics and Biometry, Fondazione IRCCS Policlinico San Matteo, University of Pavia, Italy; 2 Pulmonary Division, University Hospital of Zurich, Switzerland; 3 Molecular Epidemiology/Cancer Registry, Institutes of Social and Preventive Medicine and Clinical Pathology, University of Zurich, Switzerland; 4 Institute of Clinical Chemistry, University Hospital of Zürich, Switzerland;5 Division of Medical Molecular Genetics and Gene Diagnostics, Institute of Medical Genetics, University of Zurich, Switzerland; 6 Zürcher Höhenklinik Wald, Switzerland; 7 Division of Pulmonary Medicine, University Hospitals of Geneva, Geneva, Switzerland.

aAddress correspondence to this author at: University Hospital Zürich, Vogelsangstr. 10, 8091 Zürich, Switzerland. Fax 0041-44-255-56-36; e-mail Nicole.Probst{at}usz.ch.


   Abstract
Top
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Background: Individuals with severe deficiency in serum {alpha}1-antitrypsin (AAT) concentrations are at high risk for developing chronic obstructive pulmonary disease (COPD), whereas those carrying the PI*MZ genotype are at slightly increased risk. Testing appropriate subgroups of the population for AAT deficiency (AATD) is therefore an important aspect of COPD prevention and timely treatment. We decided to perform an exhaustive investigation of SERPINA1 gene variants in individuals from the general population with a moderately reduced serum AAT concentration, because such information is currently unavailable.

Methods: We determined the Z and S alleles of 1399 individuals enrolled in the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA) with serum AAT concentrations ≤1.13 g/L and submitted 423 of these samples for complete exon 2->5 sequencing.

Results: We found that 900 of 1399 samples (64%), carried the normal PI*MM genotype, whereas 499 samples (36%) carried at least 1 SERPINA1 deficiency variant. In the subpopulations in which AAT concentrations ranged from >1.03 to ≤1.13 and from >0.93 to ≤1.03 g/L, individuals with the PI*MM genotype represented the majority (86.5% and 53.8%, respectively). The PI*MS genotype was predominant (54.9%) in the AAT range of 0.83 to 0.93 g/L, whereas PI*MZ represented 76.4% in the AAT range of >0.73 to ≤0.83 g/L.

Conclusions: This analysis provided a detailed molecular definition of intermediate AATD, which would be helpful in the diagnostic setting.


   Introduction
Top
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
{alpha}1 Antitrypsin (AAT)1 is a 52-kDa glycoprotein produced by hepatocytes and, to a lesser extent, by mononuclear monocytes whose principal (but not sole) role is to efficiently inhibit neutrophil elastase (1). Serum concentrations of AAT are genetically determined by the 2 alleles of the SERPINA12 coding gene, according to a codominant modality (2). A small percentage of individuals, ranging from 1/1500 to 1/10 000 depending on ethnicity, exhibit severe AAT deficiency (AATD) due to homozygosity or compound heterozygosity for deficiency (Z, M-like alleles) or Null alleles (3). Individuals affected by AATD are at increased risk of developing pulmonary emphysema during their third to fifth decades and, to a lesser extent and later in life, chronic liver disease. Interestingly, the risk of developing pulmonary emphysema among subjects affected by severe AATD seems to be inversely correlated with serum AAT concentration (4)(5). A slightly increased risk for chronic obstructive pulmonary disease (COPD) has also been reported for some genotypes heterozygous for AATD alleles, such as PI*MZ (odds ratio 2.31 vs PI*MM individuals) (6), that are associated with less drastic reductions in serum AAT, also referred to as intermediate AATD. The serum AAT concentrations included in the intermediate AATD range from the lower limit of concentrations displayed by individuals carrying a compound Z/S heterozygosity (approximately 0.5 g/L) (4) to the lower limit of AAT concentrations in subjects carrying the normal PI*MM genotype (this limit varies from laboratory to laboratory, but usually ranges from 0.83 to 1.20 g/L) (4). This grey area of intermediate AATD remains poorly characterized in terms of correlation between SERPINA1 genotypes and serum AAT concentrations. We therefore conducted this study to provide a detailed characterization of SERPINA1 genotypes in intermediate AATD. Based on samples from the Swiss Cohort Study of Air Pollution and Lung Disease in Adults (SAPALDIA) (7)(8), we cross-sectionally examined the associations between SERPINA1 genotypes and serum AAT ≤1.13 g/L in the general population. Our main purpose was to provide a useful database for laboratory diagnosis of AATD.


   Materials and Methods
Top
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
subjects
The SAPALDIA cohort has been described (7)(8). At baseline in 1991, the SAPALDIA participants were 18–60 years old and predominantly whites of Swiss nationality. The current, cross-sectional investigation of AAT is restricted to follow-up data collected in 2002/2003 when the blood bank was established and includes 1399 subjects who donated blood, consented to genetic analyses, had valid serum AAT and high-sensitivity C-reactive protein (CRP) measurements, and exhibited a serum AAT concentration ≤1.13 g/L (see below for cutoff explanation) (See Supplemental Fig. 1 in the Data Supplement that accompanies the online version of this article at http://www.clinchem.org/content/vol54/issue8.) Ethical approval for the study was given by the central Ethics Committee of the Swiss Academy of Medical Sciences and the Cantonal Ethics Committees for each of the 8 examination areas.

serum analysis
AAT (g/L) and CRP (mg/dL) concentrations were determined by latex-enhanced immunoturbidimetric assays (Roche Diagnostics on a Roche COBAS Integra analyzer) with interassay CVs <5%. Lower limits of detection for the AAT and CRP assays were 0.21 g/L and 0.1 mg/dL, respectively, and reference values were 0.9–2 g/L and <0.8 mg/dL, respectively.

choice of the serum aat concentration range
We fixed the upper limit of the serum AAT concentration to enter the study at ≤1.13 g/L, according to our previous experience, obtained by a Beckman Coulter Array 360 System (9) with reference values for serum AAT of 0.83–1.99 g/L.

genetic investigations
Genomic DNA, extracted as described (10), was shipped to the Pavia center and divided into aliquots. The strategy selected for genotyping and sequencing is summarized in Fig. 1 .


Figure 1
View larger version (33K):
[in this window]
[in a new window]

  		Figure 1. Schematic representation of the genotyping/sequencing strategy followed in the study and summary of the results for each path.

Genotyping for Z and S variants.
All subjects were typed for the Z and S SERPINA1 gene variants by PCR-RFLP, as described (11). Briefly, we performed PCR amplification using the primers for exon III amplification to detect the S and 213Ala/Val variants and the primers for exon V amplification to detect the Z variant (see Supplemental Table 1 in the online Data Supplement). The reactions were carried out in an I-cycler Thermal Cycler (Bio-Rad Laboratories). Using 6 U SexAI restriction enzyme (New England Biolabs), 2 µL exon III–amplified DNA were digested in a final volume of 25 µL at 37 °C for 3 h; using 3 U Hpy99I restriction enzyme (New England Biolabs), 5 µL exon V–amplified DNA were digested in a final volume of 25 µL at 37 °C for 3 h. The digested DNA samples were separated by electrophoresis in a 3% (wt/vol) agarose gel.

Sequencing.
We sequenced exons 2, 3, 4, and 5 of subjects negative for Z and S alleles (323 samples) in the presence of serum AAT concentrations ≤1.00 g/L, or when there was an inconsistent genotype/phenotype correlation, i.e., a discrepancy in a given subject between the result of the S/Z genotyping and the serum AAT concentration (see below; 27 samples). The 1.00 g/L cutoff for sequencing was modified based on CRP concentration, according to the following protocol:

Moreover, 73 samples positive for S or Z alleles and with a consistent AAT concentration were randomly sequenced as quality controls.

Amplicons were directly sequenced in an automatic genetic analyzer (CEQ 8800 Genetic Analyzer; Beckman-Coulter). Primers used are shown in Supplemental Table 1 in the online Data Supplement.

statistical analysis
We used the Shapiro-Wilk test to test the distributions of quantitative variables for normality. We used mean, SD, and 95% CI as summary statistics for quantitative variables, Student t test for independent samples, and ANOVA (with Bonferroni correction for post hoc assessment) for comparisons between groups. We evaluated the AAT cutoff concentrations able to discriminate between samples with or without deficiency genotypes using ROC analysis (12); P < 0.05 was considered statistically significant, and all tests were 2-sided. We used Statistica 6.0 (Statsoft, Inc.) for statistical computations.


   Results
Top
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
The distribution of SERPINA1 genotypes detected in the current cross-sectional genotype–phenotype correlation study of 1399 SAPALDIA subjects with a serum AAT concentration ≤1.13 g/L is shown in Supplemental Fig. 2 in the online Data Supplement. Estimated lower limits of AATD allele prevalences, assuming the absence of S- and Z-alleles in subjects of the base population with serum AAT >1.13 g/L, were as follows: S prevalence 3% (324 S alleles in base population of 11 960 alleles/5980 subjects); Z prevalence 1% (158 Z alleles in base population of 11 960 alleles/5980 subjects) (Table 1 ). Among the subjects selected for genetic analysis (AAT ≤1.13 g/L), allele prevalences for M-, S-, Z-, and rare non-Z/non-S variants were 81%, 12%, 6%, and 1%, respectively (see also Supplemental Table 2 in the online Data Supplement).


View this table:
[in this window]
[in a new window]

  		Table 1. Summary of samples carrying deficiency SERPINA1 variants.

The normal PI*MM genotype was detected in 900 of 1399 samples (64%) (Fig. 1Up ). In 612 samples not submitted for sequencing [mean (SD) serum AAT concentration 1.088 (0.034) g/L], we detected 358 subjects carrying the M1Val213/M1Val213 combination, 217 carrying M1Ala213/M1Val213, and 37 carrying M1Ala213/M1Ala213. We sequenced 288 PI*MM samples [serum AAT concentration 1.036 (0.074) g/L]: 80 were M1Val213/M1Val213, 53 M1Ala213/M1Val213, and 10 M1Ala213/M1Ala213; 145 samples carried varying combinations of different SERPINA1 normal variants (see Supplemental Table 3 in the online Data Supplement). Molecular details are described in Table 2 .


View this table:
[in this window]
[in a new window]

  		Table 2. Molecular characterization of AAT variants.1

Subjects heterozygous for the SERPINA1 deficiency allele S ranked second in terms of prevalence (Table 1Up ; Fig. 1Up ). This series consisted of 297 subjects who had a serum AAT concentration of 1.00 (0.081) g/L. The third largest group (144 individuals) was heterozygous for the SERPINA1 deficiency allele Z and had a serum AAT concentration of 0.812 (0.114) g/L (Table 1Up and Fig. 1Up ; for molecular details, see Table 2Up ).

The remaining 3 groups were considerably smaller (Table 1Up and Table 2Up ). We identified 27 subjects as heterozygous for a rare SERPINA1 deficiency allele who had a serum AAT concentration of 0.93 (0.11) g/L. The second group is perhaps the most interesting of the 3, in spite of the small number of subjects (n = 24). This group includes subjects carrying 2 SERPINA1 deficiency alleles in a homozygous or compound heterozygous fashion. In this group, we found only 1 individual with PI*ZZ, but 10 with PI*SZ and 8 with PI*SS genotypes. Their serum AAT concentration was 0.68 (0.17) g/L. The third group included 7 subjects with 3 novel SERPINA1 mutations in combination with 1 normal M allele and a serum AAT concentration of 0.92 (0.10) g/L. One of these novel mutations was also found in combination with an S allele.

An overview of the relationship between particular SERPINA1 genotypes and serum AAT concentrations is presented in Table 3 . Statistically significant differences in AAT concentrations among MM (although referring to a subset of PI*MM individuals with a serum AAT concentration ≤1.13 g/L), MS, and MZ genotypes were observed. When the samples were stratified by CRP serum concentrations (≤ vs >0.8 mg/dL), we observed higher AAT concentrations in both MS and MZ genotype groups in the presence of CRP >0.8 mg/dL.


View this table:
[in this window]
[in a new window]

  		Table 3. SERPINA1 genotypes and corresponding serum AAT levels.

Subsequently we verified whether the 1.13 g/L cutoff for AAT, previously identified in a rather small study population (9), was indeed suitable to detect the majority of AATD variants. Using the upper limit of 1.13 g/L, AAT serum concentrations were normally distributed in the group of PI*MZ genotypes (see Supplemental Fig. 2A in the online Data Supplement) as well as among the 27 subjects heterozygous for rare AATD alleles (see Supplemental Fig. 2C in the online Data Supplement), suggesting that genotypes in these groups were exhaustively identified. In contrast, the AAT serum distribution of PI*MS samples (see Supplemental Fig. 2B in the online Data Supplement) was slightly shifted toward the right. This suggests that we failed to identify a few PI*MS subjects with the 1.13 g/L cutoff. The ROC analysis for PI*MZ showed the greatest sensitivity (83.97%) and specificity (94.21%) at the AAT serum concentration of 0.90 g/L, whereas for PI*MS variants, an AAT serum concentration of 1.03 g/L had the best sensitivity (66.34%) and specificity (66.82%) (see Supplemental Fig. 4, a and b, in the online Data Supplement for details).

We evaluated the percentage of subjects from each defined genotype class in 5 categories of AAT serum concentrations covering a 10 mg/dL range each, with the exception of the category that spans from 0 to 0.73 g/L (Fig. 2 ). In the samples in which the AAT concentration ranged from 1.13 to 1.03 g/L and from 1.03 to 0.93 g/L, PI*MM individuals represented the majority (86.5% and 53.8%, respectively). In the AAT range of 0.93 to 0.83 g/L, the majority of subjects were PI*MS (54.9%), whereas PI*MZ represented 76.4% in the AAT range of 0.83 to 0.73 g/L. PI*SZ individuals were detected only ≤0.73 g/L. Interestingly, below the 0.93 g/L limit, 15% of samples carried the normal PI*MM genotype.


Figure 2
View larger version (28K):
[in this window]
[in a new window]

  		Figure 2. Frequency (%) of 5 genotypes (PI*MM, PI*MS, PI*MZ, PI*SS, PI*SZ) stratified by AAT serum concentration ranges.

The number of subjects included in each category was 829 (1.13->1.03), 304 (1.03->0.93), 102 (0.93->0.83), 72 (0.83->0.73), and 52 (0.73->0).


   Discussion
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
To our knowledge, this is the largest study conducted in the general population to characterize intermediate AAT deficiency at the molecular level. We found that 499 (36%) of subjects with serum AAT ≤1.13 g/L carried at least 1 AATD variant.

COPD affects 4% to 7% of the general population but often remains underdiagnosed (13). Testing appropriate subgroups of the population for genetic variants in SERPINA1 would help diminish underdiagnosis. The American Thoracic Society/European Respiratory Society (ATS/ERS) 2003 document containing the standards for diagnosis and management of AATD individuals recommends diagnostic testing for all patients with COPD, asthma, unexplained liver disease, and necrotizing panniculitis, as well as for asymptomatic subjects with persistent airflow limitation and siblings of AATD individuals (4). The first decisional step in the diagnostic algorithm is the AAT serum concentration. It is therefore important to identify an appropriate cutoff that balances unnecessary costs and the exhaustive identification of deficiency alleles in the general population.

A conservative approach would suggest submitting only samples with severe AATD (<0.50 g/L) to the next diagnostic steps (4). According to our results, this limit would miss almost all PI*SZ, SS, MS, and MZ individuals. In a small study of 114 samples, we previously identified 1.13 g/L as the limit to detect AATD genotypes with a 92% sensitivity and 90% specificity (9). The present study confirms this finding in a much larger sample. The 1.13 g/L limit allowed us to detect all PI*MZ individuals (Table 1Up ; Supplemental Fig. 3A in the online Data Supplement); at the AAT concentration of 0.90 g/L, we estimated sensitivity and specificity at 94% and 83%, respectively (see Supplemental Fig. 4a in the online Data Supplement). However, we estimated that the same limit did not prevent missing 10%–15% of PI*MS samples (Table 1Up ; Supplemental Fig. 3B in the online Data Supplement). For this genotype, we calculated a sensitivity and specificity of only 66% and 67%, respectively, at an AAT concentration of 1.03 g/L (see Supplemental Fig. 4b in the online Data Supplement).

The situation seems similar for the small and heterogeneous group of individuals carrying 1 rare AATD allele (Table 1Up ; Supplemental Fig. 3C in the online Data Supplement). We were not able to perform equivalent calculations for subjects carrying a novel, putative AATD variant (Table 2Up ) because of the very small sample size (n = 7). But we postulate that the 1.13 g/L limit misses a comparable percentage of these genotypes, because the AAT serum concentration in this group [0.92 (0.10) g/L] is close to that of heterozygotes for a rare AATD variant [0.93 (0.11) g/L]. Other rare genotype classes, including PI*SS, are unlikely to be missed with the 1.13 g/L cutoff.

The clinical relevance of an exhaustive identification of AATD alleles in the general population is emphasized by their prevalence, which is not negligible. The estimated prevalences of MS, MZ, SZ, SS, and ZZ genotypes in the SAPALDIA cohort are 5.0%, 2.4%, 0.2%, 0.1%, and 0.02%, respectively. As we may not have recognized the presence of a few additional deficiency alleles in the absence of sequencing results for all participants, these prevalence estimates must be regarded as a lower limit. The very limited number of subjects identified as affected by severe AATD hindered us from drawing firm conclusions about this category. At least some of the AATD genotypes that would be missed with an AAT serum cutoff lower than 1.13 g/L are at increased risk of developing COPD. While the association of PI*MS or carriage of rare AATD variants with the risk of COPD remains unclear (14)(15)(16), the PI*MZ genotype can be considered as an identified genetic risk factor for COPD (6)(14)(17)(18)(19). PI*MZ individuals have been shown to contribute substantially to hospitalization for COPD in Denmark (20), if they are a first-degree relative of PI*ZZ index cases. More recently, in the same country, the association has been demonstrated between the PI*MZ genotype with reduced lung function in individuals with COPD (17) and with an accelerated decline in forced expiratory volume in 1 s (FEV1) (21) in the general population.

Our investigation confirmed the presence of a group of individuals carrying a rare, non-S and non-Z, AATD allele. These rare alleles represent 7% of all AATD alleles detected in this study. We have previously developed a special interest in the prevalence of rare AATD variants in Italy: among individuals affected by severe AATD, we detected an 11% prevalence (updated April 2004) of subjects with AATD genotypes other than PI*ZZ or PI*SZ (5). In a recently published paper from the A.I.R. (AlphaOne International Registry), which includes data from 4 continents and 21 countries, predominantly in Europe, the frequency of rare AATD variants was 4.7% (updated March 2006) (22). Among heterozygous carriers in Italy only, the updated rare AATD allele frequency is 9.2% of all AATD deficiency alleles (16). A very recent report from the Netherlands has addressed this point: sequence analysis of 66 DNA samples from patients with low plasma AAT revealed the presence of 10 rare M-like or Null SERPINA1 variants, including 2 Null variants previously unidentified (23). The authors conclude that up to 22% of deficiency variants may be missed by conventional diagnostic methods. Because the rare variants represent a challenge for the laboratory diagnosis of AATD (24), we cannot exclude that their prevalence was thus far underestimated owing to technical issues.

One strength of this study is that the samples were collected from the general population, and detailed characterization of participants included data on their CRP serum concentrations. Considering that inflammation is an intrinsic factor potentially influencing the AAT serum concentration (25), we corrected the AAT serum concentration for CRP. We observed, as expected, a decrease in the mean AAT serum concentration for PI*MS and PI*MZ genotype classes in samples with CRP serum concentrations below the limit of 0.8 mg/dL (Table 2Up ). Increased CRP serum concentrations have been recently associated with COPD. CRP has been proposed as a biomarker for monitoring the systemic consequences of the inflammatory status in COPD (26)(27). In the population investigated in the Copenhagen City Heart Study, mean AAT serum concentrations in individuals from all genotypical classes who had never smoked were slightly lower than in all participants (21); this is consistent with the influence of systemic inflammation on AAT concentrations in blood. The interplay between AAT and CRP concentrations needs further investigation, and must be taken into account when upper limits of AAT serum concentrations are considered. It is conceivable that variation in adjustment for inflammatory status also underlies some of the observed differences in the ranges for serum AAT concentrations between our study and the ATS/ERS document (4). For the 2 genotype classes, i.e., PI*SZ and PI*MZ, that are likely to be included in their entirety within the limit of 1.13 g/L, the AAT serum concentration ranges (first to 99th percentile) were 0.49 to 0.66 g/L for PI*SZ and 0.63 to 1.10 g/L for PI*MZ. Accordingly, values reported in the ATS/ERS document (4) ranged from 0.75 to 1.20 g/L for PI*SZ and from 0.90 to 2.10 g/L for PI*MZ. As these values were derived from data published between 1981 and 1991 (28)(29)(30), it is possible that they have been influenced by lack of laboratory standardization (30)(31).

In conclusion, this paper exhaustively characterizes the SERPINA1 gene variants associated with reduced serum AAT concentrations. The proposed upper AAT limit of 1.13 g/L in the serum allowed us to detect approximately 95% of AATD variants, whereas those presumably missed were likely irrelevant cases. We believe that, besides identifying severely affected AATD subjects, it is an important public health commitment to also unambiguously identify PI*MZ carriers and possibly additional intermediate deficiency allele carriage. These genotypes are not rare, and at least some are linked with an increased risk for COPD. It is conceivable that the awareness of carrying a risk variant in SERPINA1 would increase patient compliance with physicians’ advice not to smoke (32). Our current study provides ranges of serum AAT concentrations for given genotypes, such as PI*MZ or PI*MS, narrower than those available in the past, and it emphasizes as well that systemic inflammatory status may influence the AAT concentration. It also shows that, in spite of extensive sequencing, a substantial number of samples categorized as "normal" PI*MM actually overlap, in terms of AAT concentration, with other defined genotypes. This finding suggests that PI*MM would be in these cases a diagnosis of exclusion, and that the current categorization of SERPINA1 variants might be improved in the future.


   Acknowledgments
 
Grant/Funding Support: The research has been supported by Olga-Mayenfisch Stiftung Zürich, the Swiss National Science Foundation (grants NF32-65896.01, NF32-58996.99, NF32-54996.98), Freiwillige Akademische Gesellschaft Basel, Lung Leagues of Basel-Stadt/Basel-Landschaft/Geneva/Ticino/Zurich and Lung League of Switzerland, Federal Offices for Forest, Environment and Lanscape/for Public Health/for Roads and Transport, Cantons of Aargau, Basel-Stadt, Basel-Land, Geneva, Luzern, Ticino, Zurich. The Center for Diagnosis of Severe Alpha1 Antitrypsin Deficiency in Pavia, Italy, has been supported by grants from the Fondazione IRCCS San Matteo (Ricerca Corrente), Fondazione CARIPLO, Istituto Superiore di Sanità grants for Rare Diseases 2005, and an unrestricted grant form Talecris Biotherapeutics, Germany. O. Senn and I. Ferrarotti were recipients of eALTA fellowships in 2004 and 2006, respectively.

Financial Disclosures: E. Russi and M. Luisetti are members of the council of A.I.R. (Alpha1 International Registry).

Acknowledgments: The study could not have been completed without the help of the study participants, technical and administrative support, and the medical teams and field workers at the local study sites.


   Footnotes
 
1 Nonstandard abbreviations: AAT, {alpha}1-antitrypsin; AATD, AAT deficiency; COPD, chronic obstructive pulmonary disease; SAPALDIA, Swiss Cohort Study on Air Pollution and Lung Diseases in Adults; CRP, C-reactive protein.

2 Human gene: SERPINA1, serpin peptidase inhibitor, clade A ({alpha}-1 antiproteinase, antitrypsin), member 1.


   References
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Silverman GA, Bird PI, Carrell RW, Church FC, Coughlin PB, Gettings PGW, et al. The serpins are an expanding superfamily of structurally similar but functionally diverse proteins. J Biol Chem 2001;276:33293-33296.[Free Full Text]
  2. Brantly M. Alpha1-antitrypsin genotypes and phenotypes. Crystal RG eds. Alpha1-Antitrypsin Deficiency 1996:45-59 Marcel Dekker New York. .
  3. Luisetti M, Seershol N. Alpha1-antitrypsin deficiency. 1: epidemiology of alpha1 antitrypsin deficiency. Thorax 2004;59:164-169.[Abstract/Free Full Text]
  4. . American Thoracic Society/European Respiratory Society Statement. Standards for the diagnosis and management of individuals with alpha1-antitrypsin deficiency. Am J Respir Crit Care Med 2003;168:818-900.[Free Full Text]
  5. Ferrarotti I, Baccheschi J, Zorzetto M, Tinelli C, Corda L, Balbi B, et al. Prevalence and phenotype of subjects carrying rare variants in the Italian registry for alpha1-antitrypsin deficiency. J Med Genet 2005;42:282-287.[Free Full Text]
  6. Hersh CP, Dahl M, Ly NP, Berkey CS, Nordestgaard BG, Silverman EK. Chronic obstructive pulmonary disease in {alpha}1-antitrypsin PI MZ heterozygotes: a meta-analysis. Thorax 2004;59:843-849.[Abstract/Free Full Text]
  7. Martin BW, Ackermann-Liebrich U, Leuenberger P, Kunzli N, Stutz EZ, Keller R, et al. SAPALDIA: methods and participation in the cross-sectional part of the Swiss Study on Air Pollution and Lung Diseases in Adults. Soz Praventivmed 1997;42:67-84.[Web of Science][Medline] [Order article via Infotrieve]
  8. Ackermann-Liebrich U, Kuna-Dibbert B, Probst-Hensch NM, Schindler C, Dietrich DF, Stutz EZ, et al. Follow-up of the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA 2) 1991–2003: methods and characterization of participants. Soz Praventivmed 2005;50:1-19.[CrossRef][Web of Science]
  9. Gorrini M, Ferrarotti I, Lupi A, Bosoni T, Mazzola P, Scabini R, et al. Validation of a rapid, simple method to measure {alpha}1-antitrypsin in human dried blood spots. Clin Chem 2006;52:899-901.[Free Full Text]
  10. Imboden M, Downs SH, Senn O, Matyas G, Brändli O, Russi EW, et al. Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study. Respir Res 2007;8:2.[CrossRef][Medline] [Order article via Infotrieve]
  11. Ferrarotti I, Zorzetto M, Scabini R, Mazzola P, Campo I, Luisetti M. A novel method for rapid genotypic identification of alpha1-antitrypsin variants. Diagn Mol Pathol 2004;12:160-163.[Web of Science]
  12. Metz CE. Basic principles of ROC analysis. Semin Nucl Med 1978;8:283-298.[Web of Science][Medline] [Order article via Infotrieve]
  13. Celli BR, MacNee W, Agusti A, Anzueto A, Berg B, Buist AS, et al. Standards for diagnosis and treatment of patients with COPD: a summary of the ATS/ERS position paper. Eur Respir J 2004;23:932-946.[Free Full Text]
  14. Senn O, Russi EW, Imboden M, Probst-Hensch NM. Alpha1-Antitrypsin deficiency and lung disease: risk modification by occupational and environmental inhalants. Eur Respir J 2005;26:1-9.[Free Full Text]
  15. Dahl M, Hersh CP, Ly NP, Berkey CS, Silverman EK, Nordestgaard BG. The protease inhibitor PI*S allele and COPD: a meta-analysis. Eur Respir J 2005;26:67-76.[Abstract/Free Full Text]
  16. Ferrarotti I, Gorrini M, Scabini R, Ottaviani S, Mazzola P, Campo I, et al. Secondary outputs of alpha1-antitrypsin deficiency targeted detection programme. Respir Med 2008;102:354-358.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]
  17. Dahl M, Nordestgaard BG, Lange P, Vestbo J, Tybjærg-Hansen A. Molecular diagnosis of intermediate and severe {alpha}1-antitrypsin deficiency: MZ individuals with chronic obstructive pulmonary disease may have lower lung function than MM individuals. Clin Chem 2001;47:56-62.[Abstract/Free Full Text]
  18. Silverman EK, Province MA, Campbell EJ, Pierce JA, Rao DC. Family study of {alpha}1-antitrypsin deficiency: effects of cigarette smoking, measured genotype, and their interaction on pulmonary function and biochemical traits. Genet Epidemiol 1992;9:317-331.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]
  19. Eriksson S, Lindell SE, Wiberg R. Effects of smoking and intermediate {alpha}1-antitrypsin deficiency (PiMZ) on lung function. Eur J Respir Dis 1985;67:279-285.[Web of Science][Medline] [Order article via Infotrieve]
  20. Seersholm N, Wilcke JT, Kok-Jensen A, Dirksen A. Risk of hospital admission for obstructive pulmonary disease in {alpha}1-antitrypsin heterozygotes of phenotype PiMZ. Am J Respir Crit Care Med 2000;16:81-84.
  21. Dahl M, Tybjærg-Hansen A, Lange P, Vestbo J, Nordestgaard BG. Change in lung function and morbidity from chronic obstructive pulmonary disease in {alpha}1-antitrypsin MZ heterozygotes: a longitudinal study of the general population. Ann Intern Med 2002;136:270-279.[Abstract/Free Full Text]
  22. Stockley RA, Luisetti M, Miravitlles M, Piituilanen E, Fernandez P, . AIR group. Ongoing research in Europe: Alpha One International Registry (AIR) objectives and development. Eur Respir J 2007;29:582-586.[Abstract/Free Full Text]
  23. Prins J, van der Maijden BB, Kraaijenhagen RJ, Wielders JPM. Inherited chronic obstructive pulmonary disease: new selective-sequencing workup for {alpha}1-antitrypsin deficiency identifies 2 previously unidentified Null alleles. Clin Chem 2008;54:101-107.[Abstract/Free Full Text]
  24. Ferrarotti I, Scabini R, Campo I, Ottaviani S, Zorzetto M, Gorrini M, Luisetti M. Laboratory diagnosis of alpha1-antitrypsin deficiency. Transl Res 2007;150:267-274.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]
  25. Travis J, Salvesen GS. Human plasma proteinase inhibitors. Annu Rev Biochem 1983;52:655-709.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]
  26. Pinto-Plata VM, Mullerova H, Toso JF, Feudo-Tepie M, Soriano JB, Vessey RS, Celli BR. C-reactive protein in patients with COPD, control smokers, and non-smokers. Thorax 2006;61:23-28.[Abstract/Free Full Text]
  27. Dahl M, Vestbo J, Lange P, Bojesen SE, Tybjaerg-Hensen A, Nordestgaard BG. C-reactive protein as predictor of prognosis in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2007;175:250-255.[Abstract/Free Full Text]
  28. Fagerol MK, Cox DW. The Pi polymorphism: genetic, biochemical and clinical aspects of alpha1-antitrypsin deficiency. Adv Hum Genet 1981;11:1-62.[Medline] [Order article via Infotrieve]
  29. Brantly M, Nukiwa T, Crystal RG. Molecular basis of {alpha}1-antitrypsin deficiency. Am J Med 1988;84(Suppl 6A):13-31.[Web of Science][Medline] [Order article via Infotrieve]
  30. Brantly ML, Wittes JT, Vogelmeier CF, Hubbard RC, Fells GA, Crystal RG. Use of a highly purified alpha1-antitrypsin standard to establish ranges for the common normal and deficient alpha1-antitrypsin phenotypes. Chest 1991;100:703-708.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]
  31. Seal LA, Carp DA, George RB. Comparison of commercially available radial immunodiffusion kits for the determination of serum {alpha}1-antitrypsin concentration. Am Rev Respir Dis 1975;111:97-100.[Web of Science][Medline] [Order article via Infotrieve]
  32. Carpenter MJ, Strange C, Jones Y, Dickson MR, Carter C, Moseley MA, Gilbert GE. Does genetic testing result in behavioral health change? Changes in smoking behavior following testing for alpha1 antitrypsin deficiency. Ann Behav Med 2007;33:22-28.[CrossRef][Web of Science][Medline] [Order article via Infotrieve]



The following articles in journals at HighWire Press have cited this article:


Home page
 Clin. Chem.Home page
M. R. Snyder and W. E. Highsmith Jr
Commentary
Clin. Chem., August 1, 2008; 54(8): 1399 - 1399.
[Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Supplement Data
Right arrow All Versions of this Article:
clinchem.2007.102798v1
54/8/1331    most recent
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Zorzetto, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zorzetto, M.
Related Collections
Right arrow Molecular Diagnostics and Genetics

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS