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Blanco I, Miravitlles M. Genetic Epidemiology of Alpha-1 Antitrypsin Deficiency in Macaronesia. Respiration 2024; 103:368-377. [PMID: 38588657 DOI: 10.1159/000538293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/06/2024] [Indexed: 04/10/2024] Open
Abstract
INTRODUCTION The prevalence of alpha-1 antitrypsin deficiency (AATD) in Macaronesia (i.e., Azores, Madeira, Canary Islands, and Cape Verde archipelagos) is poorly known. Our goal was to update it by selecting the most reliable available articles. METHOD Literature search using MEDLINE, Embase (via Ovid), and Google Scholar, until December 2023, for studies on prevalence of AATD in the general population and in screenings, published in peer-reviewed journals. RESULTS Three studies carried out in the general population of Madeira, La Palma, and Cape Verde, and three screenings carried out in La Palma (2) and Gran Canaria (1) were selected. The frequencies of PI*S in the general population showed an ascending gradient, from South to North, with values (per thousand) of 35 in Cape Verde, 82 in La Palma, and 180 in Madeira. The PI*Z frequencies showed this same gradient, with values of 2 × 1,000 in Cape Verde, 21 in La Palma, and 25 in Madeira. Screenings detected high percentages of defective alleles, including several rare and null alleles, some unique to these islands. CONCLUSION The frequencies of PI*S and PI*Z in Madeira are comparable to the highest in the world. Those of the Canary Islands are similar to those of the peninsular population of Spain, and contrast with the low rates of Cape Verde. Screenings detected high numbers of deficient alleles. These results support the systematic investigation of AATD in clinically suspected patients and in relatives of index cases, to reduce underdiagnosis and apply early preventive and therapeutic measures in those affected.
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Affiliation(s)
- Ignacio Blanco
- Hospital Valle del Nalón, Pneumology Service (retired), Langreo, Spain
| | - Marc Miravitlles
- Pneumology Department, Hospital Universitari Vall d'Hebron/Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
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Hernández‐Pérez JM, López‐Charry CV. Is the determination of C‐reactive protein really necessary in the diagnosis of Alpha‐1 antitrypsin deficiency? THE CLINICAL RESPIRATORY JOURNAL 2022; 16:420-422. [PMID: 35578817 PMCID: PMC9366562 DOI: 10.1111/crj.13494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/06/2022] [Accepted: 05/09/2022] [Indexed: 11/29/2022]
Affiliation(s)
- José María Hernández‐Pérez
- Department of Neumology Hospital Universitario Nuestra Señora de Candelaria Santa Cruz de Tenerife Spain
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Frequency of alleles and genotypes associated with alpha-1 antitrypsin deficiency in clinical and general populations: Revelations about underdiagnosis. Pulmonology 2022; 29:214-220. [PMID: 35346640 DOI: 10.1016/j.pulmoe.2022.01.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Alpha-1 antitrypsin deficiency (AATD) is an underdiagnosed hereditary condition that promotes the development of lung and liver diseases, and the most common potentially life-threatening genetic condition in Caucasian adults. In this study, the clinical and genetic profile of pulmonary patients from a single center in La Palma Island (Canary Islands, Spain) was assessed to predict how to increase AATD diagnosis. METHODS AATD was tested in 1,493 pulmonary outpatients without regard to respiratory symptoms and 465 newborns. Variants of the SERPINA1 gene were characterised by real-time PCR, DNA sequencing, molecular haplotyping and phenotyping (AAT isoelectric focusing). Different respiratory pathologies were diagnosed in patients and their levels of serum AAT were measured by nephelometry. RESULTS The prevalence of pneumological patients with AATD alleles was 30.5%, including PI*S, PI*Z and 6 rare genetic variants. Certain deficiency genotypes were unevenly distributed among patients diagnosed with respiratory diseases: PI*ZZ (71.4%) and PI*SS (34.8%) genotypes were more represented in patients with chronic obstructive pulmonary disease (COPD), whereas PI*MZ (27.7%) and PI*SZ (34.5%) genotypes were more abundant in patients with bronchial asthma. The estimated frequency of PI*S and PI*Z alleles in the general population was 8.2% and 2.1%, respectively. A very significant enrichment (p< 0.01) of PI*S allele, independent of the PI*Z allele, was detected in the clinical population. CONCLUSIONS AATD diagnosis would improve if both the COPD and the asthmatic patients were included to screening programs. The prevalence of PI*ZZ genotype in La Palma (1/2,162) was relatively high within Spain (average 1/3,344).
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Foil KE. Variants of SERPINA1 and the increasing complexity of testing for alpha-1 antitrypsin deficiency. Ther Adv Chronic Dis 2021; 12_suppl:20406223211015954. [PMID: 34408833 PMCID: PMC8367212 DOI: 10.1177/20406223211015954] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 04/20/2021] [Indexed: 02/06/2023] Open
Abstract
Alpha-1 antitrypsin deficiency (AATD) is caused by mutations in the SERPINA1 gene, which encodes the alpha-1 antitrypsin (AAT) protein. Currently, over 200 SERPINA1 variants have been identified, many of which cause the quantitative and/or qualitative changes in AAT responsible for AATD-associated lung and liver disease. The types of these pathogenic mutations are varied, often resulting in misfolding, or truncating of the AAT amino acid sequence, and improvements in sequencing technology are helping to identify known and novel genetic variants. However, due to the diversity and novelty of rare variants, the clinical significance of many is largely unknown. There is, therefore, a lack of guidance on how patients should be monitored and treated when the clinical significance of their variant combination is unclear or variable. Nevertheless, it is important that physicians understand the advantages and disadvantages of the different testing methodologies available to diagnose AATD. Owing to the autosomal inheritance of the genetic mutations responsible for AATD, genetic testing should be offered not only to patients at increased AATD risk (e.g. patients with chronic obstructive pulmonary disease), but also to relatives of those with an abnormal result. Genetic counseling may help patients and family members understand the possible outcomes of testing and the implications for the family. While stress/anxiety can arise from genetic diagnosis or confirmation of carrier status, there can be positive consequences to genetic testing, including improved lifestyle choices, directed medical care, and empowered family planning. As genetic testing technology grows and becomes more popular, testing without physician referral is becoming more prevalent, irrespective of the availability of genetic counseling. Therefore, the Alpha-1 Foundation offers genetic counseling, as well as other support and educational material, for patients with AATD, as well as their families and physicians, to help improve the understanding of potential benefits and consequences of genetic testing.
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Affiliation(s)
- Kimberly E Foil
- Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
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Seixas S, Marques PI. Known Mutations at the Cause of Alpha-1 Antitrypsin Deficiency an Updated Overview of SERPINA1 Variation Spectrum. APPLICATION OF CLINICAL GENETICS 2021; 14:173-194. [PMID: 33790624 PMCID: PMC7997584 DOI: 10.2147/tacg.s257511] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 02/24/2021] [Indexed: 12/12/2022]
Abstract
Alpha-1-Antitrypsin deficiency (AATD), caused by SERPINA1 mutations, is one of the most prevalent Mendelian disorders among individuals of European descend. However, this condition, which is characterized by reduced serum levels of alpha-1-antitrypsin (AAT) and associated with increased risks of pulmonary emphysema and liver disease in both children and adults, remains frequently underdiagnosed. AATD clinical manifestations are often correlated with two pathogenic variants, the Z allele (p.Glu342Lys) and the S allele (p.Glu264Val), which can be combined in severe ZZ or moderate SZ risk genotypes. Yet, screenings of AATD cases and large sequencing efforts carried out in both control and disease populations are disclosing outstanding numbers of rare SERPINA1 variants (>500), including many pathogenic and other likely deleterious mutations. Generally speaking, pathogenic variants can be subdivided into either loss- or gain-of-function according to their pathophysiological effects. In AATD, the loss-of-function is correlated with an uncontrolled activity of elastase by its natural inhibitor, the AAT. This phenomenon can result from the absence of circulating AAT (null alleles), poor AAT secretion from hepatocytes (deficiency alleles) or even from a modified inhibitory activity (dysfunctional alleles). On the other hand, the gain-of-function is connected with the formation of AAT polymers and their switching on of cellular stress and inflammatory responses (deficiency alleles). Less frequently, the gain-of-function is related to a modified protease affinity (dysfunctional alleles). Here, we revisit SERPINA1 mutation spectrum, its origins and population history with a greater emphasis on variants fitting the aforementioned processes of AATD pathogenesis. Those were selected based on their clinical significance and wider geographic distribution. Moreover, we also provide some directions for future studies of AATD clinically heterogeneity and comprehensive diagnosis.
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Affiliation(s)
- Susana Seixas
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
| | - Patricia Isabel Marques
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
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Bellemare J, Gaudreault N, Valette K, Belmonte I, Nuñez A, Miravitlles M, Maltais F, Bossé Y. The Clinical Utility of Determining the Allelic Background of Mutations Causing Alpha-1 Antitrypsin Deficiency: The Case with the Null Variant Q0(Mattawa)/Q0(Ourém). CHRONIC OBSTRUCTIVE PULMONARY DISEASES-JOURNAL OF THE COPD FOUNDATION 2021; 8. [PMID: 33150777 DOI: 10.15326/jcopdf.8.1.2020.0168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Background Alpha-1 antitrypsin deficiency (AATD) is caused by genetic variants in the SERPINA1 gene conferring risk of developing emphysema. The clinical expression of AATD-related emphysema mostly occurs in carriers of 2 deficient alleles. By DNA sequencing of SERPINA1, numerous rare variants have been identified. Clarifying whether 2 mutations observed in 1 patient are on the same or distinct alleles has obvious clinical implications. Methods We studied 7 carriers of a rare variant, Leu353Phe_fsTer24, known to lead to undetectable serum levels of AAT. Two of them were also carriers of the S or Z allele. We developed an allele-specific DNA sequencing method to characterize the allelic background of the Leu353Phe_fsTer24 variant. Results The Leu353Phe_fsTer24 variant was transmitted on the same allele as the M3 variant (E376D) in all patients. This mutation is thus named Q0Ourém on the conventional PI system. We demonstrated that individuals harboring the E264V (S) and E342K (Z) mutations had them on distinct alleles from Q0Ourém and are, thus, compound heterozygotes. The 7 Q0Ourém carriers had AAT levels ranging from 0.18g/l to 0.82g/l. The lowest AAT serum levels were observed in compound heterozygotes (S/Q0Ourém and Z/Q0Ourém) suggesting higher risk of developing emphysema. Conclusion For the 7 patients, Leu353Phe_fsTer24 is transmitted on the M3 background and they are, thus, carriers of the Q0Ourém allele. Allele-specific DNA sequencing was useful to distinguish 1 or 2 deficient alleles in carriers of 2 mutations. In rare cases, this method is important to understand the clinical significance of genetic variants found in SERPINA1.
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Affiliation(s)
- Judith Bellemare
- Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Nathalie Gaudreault
- Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Kim Valette
- Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Irene Belmonte
- Pneumology Department, Hospital Universitari Vall d´Hebron, Vall d´Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain
| | - Alexa Nuñez
- Pneumology Department, Hospital Universitari Vall d´Hebron, Vall d´Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain
| | - Marc Miravitlles
- Pneumology Department, Hospital Universitari Vall d´Hebron, Vall d´Hebron Institut de Recerca (VHIR), Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain.,CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - François Maltais
- Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Yohan Bossé
- Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval, Québec, QC, Canada.,Department of Molecular Medicine, Laval University, Quebec City, Canada
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Hernández Pérez JM, Blanco I, Jesús Sánchez Medina A, Díaz Hernández L, Antonio Pérez Pérez J. Serum Levels of Glutamate-Pyruvate Transaminase, Glutamate-Oxaloacetate Transaminase and Gamma-Glutamyl Transferase in 1494 Patients with Various Genotypes for the Alpha-1 Antitrypsin Gene. J Clin Med 2020; 9:jcm9123923. [PMID: 33287251 PMCID: PMC7761682 DOI: 10.3390/jcm9123923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 11/27/2020] [Accepted: 12/01/2020] [Indexed: 01/04/2023] Open
Abstract
Background: Patients with liver disease associated with alpha-1 antitrypsin deficiency (AATD) are homozygous for the Z mutation, leading to chronic liver damage. Objective: To assess the serum levels of glutamate-oxaloacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT), and gamma-glutamyl transpeptidase (GGT) in patients with different genotypes for the alpha-1 antitrypsin (AAT) gene. Methods: Patients (n = 1494) underwent genotyping of the SERPINA1 gene, together with a determination of AAT and GOT and GPT and GGT transaminase levels. Patients with a deficient allele (n = 476) and with a normal genotype were compared. Results: A statistically significant association was found between deficient genotypes and GOT (p < 0.0003), GPT (p < 0.002), and GGT (p < 0.006). Comparing GOT levels in patients with PI*Z deficient variant versus those with normal genotype, an odds ratio (OR) of 2.72 (CI: 1.5–4.87) (p < 0.0005) was obtained. This finding was replicated with the PI*Z allele and the GPT values (OR = 2.31; CI: 1.45–3.67; p < 0.0003). In addition, a statistically significant association was found between liver enzymes and AAT values. Conclusion: The PI*Z allele seemed to be a risk factor for the development of liver damage. AAT deficient genotypes were associated with GOT, GPT, and GGT altered values. Low AAT levels were associated with high GPT and GGT levels.
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Affiliation(s)
- José María Hernández Pérez
- Pulmonology Department, University Hospital Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010 Canary Islands, Spain;
| | - Ignacio Blanco
- Spanish Registry of Alpha-1 Antitrypsin Deficiency (REDAAT), Respira Foundation, Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), 08029 Barcelona, Spain;
| | - Agustín Jesús Sánchez Medina
- University Institute of Sciences and Cybernetic Technologies, University of Las Palmas de Gran Canaria, 35018 Las Palmas, Spain;
| | - Laura Díaz Hernández
- Digestive System Department, University Hospital Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 38010 Canary Islands, Spain;
| | - José Antonio Pérez Pérez
- Institute of Tropical Diseases and Public Health of the Canary Islands, University of La Laguna, Genetic Area, 38206 Canary Islands, Spain
- Correspondence: ; Tel.: +34-922-316-502 (ext. 8678/6891); Fax: +34-922-318-311
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Wang C, Zhao P, Sun S, Teckman J, Balch WE. Leveraging Population Genomics for Individualized Correction of the Hallmarks of Alpha-1 Antitrypsin Deficiency. CHRONIC OBSTRUCTIVE PULMONARY DISEASES-JOURNAL OF THE COPD FOUNDATION 2020; 7:224-246. [PMID: 32726074 DOI: 10.15326/jcopdf.7.3.2019.0167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Deep medicine is rapidly moving towards a high-definition approach for therapeutic management of the patient as an individual given the rapid progress of genome sequencing technologies and machine learning algorithms. While considered a monogenic disease, alpha-1 antitrypsin (AAT) deficiency (AATD) patients present with complex and variable phenotypes we refer to as the "hallmarks of AATD" that involve distinct molecular mechanisms in the liver, plasma and lung tissues, likely due to both coding and non-coding variation as well as genetic and environmental modifiers in different individuals. Herein, we briefly review the current therapeutic strategies for the management of AATD. To embrace genetic diversity in the management of AATD, we provide an overview of the disease phenotypes of AATD patients harboring different AAT variants. Linking genotypic diversity to phenotypic diversity illustrates the potential for sequence-specific regions of AAT protein fold design to play very different roles during nascent synthesis in the liver and/or function in post-liver plasma and lung environments. We illustrate how to manage diversity with recently developed machine learning (ML) approaches that bridge sequence-to-function-to-structure knowledge gaps based on the principle of spatial covariance (SCV). SCV relationships provide a deep understanding of the genotype to phenotype transformation initiated by AAT variation in the population to address the role of genetic and environmental modifiers in the individual. Embracing the complexity of AATD in the population is critical for risk management and therapeutic intervention to generate a high definition medicine approach for the patient.
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Affiliation(s)
- Chao Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, California
| | - Pei Zhao
- Department of Molecular Medicine, Scripps Research, La Jolla, California
| | - Shuhong Sun
- Department of Molecular Medicine, Scripps Research, La Jolla, California
| | - Jeffrey Teckman
- Pediatrics and Biochemistry, Saint Louis University, and Cardinal Glennon Children's Medical Center, St. Louis, Missouri
| | - William E Balch
- Department of Molecular Medicine, Scripps Research, La Jolla, California
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Tubío-Pérez RA, Blanco-Pérez M, Ramos-Hernández C, Torres-Durán M. Alpha-1 Antitrypsin Deficiency Associated with the PI*Q0 ourém Allele in a 2-Year-old Girl and Family Study. An Unusual Case. Arch Bronconeumol 2018; 54:228-230. [PMID: 29122334 DOI: 10.1016/j.arbres.2017.09.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Ramón Antonio Tubío-Pérez
- Servicio de Neumología, Hospital Álvaro Cunqueiro, EOXI de Vigo, Vigo, Pontevedra, España; Centro galego Alfa-1-antitripsina, Galicia, España.
| | - Milagros Blanco-Pérez
- Unidad de Citogenética y Genética Molecular, Servicio de Análisis Clínicos, EOXI de Vigo, Vigo, Pontevedra, España
| | - Cristina Ramos-Hernández
- Servicio de Neumología, Hospital Álvaro Cunqueiro, EOXI de Vigo, Vigo, Pontevedra, España; Grupo de Investigación Neumovigo I+i, Instituto de Investigación Biosanitaria Galicia Sur, Vigo, Pontevedra, España; Centro galego Alfa-1-antitripsina, Galicia, España
| | - María Torres-Durán
- Servicio de Neumología, Hospital Álvaro Cunqueiro, EOXI de Vigo, Vigo, Pontevedra, España; Grupo de Investigación Neumovigo I+i, Instituto de Investigación Biosanitaria Galicia Sur, Vigo, Pontevedra, España; Centro galego Alfa-1-antitripsina, Galicia, España
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Mosella M, Accardo M, Molino A, Maniscalco M, Zamparelli AS. Description of a new rare alpha-1 antitrypsin mutation in Naples (Italy): PI*M S-Napoli. Ann Thorac Med 2018; 13:59-61. [PMID: 29387258 PMCID: PMC5772110 DOI: 10.4103/atm.atm_234_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 08/27/2017] [Indexed: 01/15/2023] Open
Abstract
Alpha-1 antitrypsin deficiency is a rare and often underdiagnosed hereditary disorder, which mainly affects the Caucasian population. We report a case of a noncystic fibrosis bronchiectasis patient in the absence of emphysema associated with low serum alpha-1-antitrypsin (AAT) level, in the absence of the most common defective alleles associated with AAT deficiency (PI*S and PI*Z) but with a new mutation in heterozygosis. This mutation is characterized by the substitution in the coding region of exon 3, of a guanine (G) for a thymine (T), generating the replacement of a glutamine (Gln) by a histidine (His) in codon 212 (cod 212 GlnCAG > HisCAT), corresponds to a new S allelic variant. This mutation, never identified before, is called S-Napoli.
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Affiliation(s)
- Marco Mosella
- Department of Clinical Medicine and Surgery, Federico II University Hospital, Naples, Italy
| | - Mariasofia Accardo
- Department of Clinical Medicine and Surgery, Federico II University Hospital, Naples, Italy
| | - Antonio Molino
- Department of Respiratory Diseases, Division of Pneumology, University of Naples Federico II, AORN dei Colli-Monaldi Hospital, Naples, Italy
| | - Mauro Maniscalco
- Department of Cardio- Respiratory Rehabilitation, Pulmonary Rehabilitation Unit, ICS Maugeri SpA SB, Institute of Telese Terme, Benevento, Italy
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Hernández Pérez JM, Blanco I. First Argentine study on alpha-1 antitrypsin deficiency in dried blood spot samples from COPD patients. Arch Bronconeumol 2015; 51:535-6. [PMID: 26143134 DOI: 10.1016/j.arbres.2015.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/06/2015] [Indexed: 11/30/2022]
Affiliation(s)
| | - Ignacio Blanco
- Neumólogo retirado, Hospital Valle del Nalón, Langreo, Asturias, España
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