A fast amplification-reverse hybridization assay kit to detect the most frequent deficient variants in the alpha-1-antitrypsin gene.
BACKGROUND
There is worldwide growing awareness of alpha-1-antitrypsin deficiency (AATD), a major hereditary disorder in Caucasians. The gold standard for its laboratory diagnosis is thin-layer isoelectric focusing, which should be performed in reference laboratories.


OBJECTIVE
The aim of this study was to check the characteristics of a commercially available amplification-reverse hybridization assay kit in detecting at a molecular level the alpha-1-antitrypsin (AAT) Z and S variants, i.e. the most frequent variants associated with AATD, by comparing its performance with DNA restriction fragment length polymorphism.


METHODS
We studied samples from 36 subjects enrolled in the Italian National Registry for Severe Alpha-1-antitrypsin Deficiency. Based on previous plasma isoelectric focusing typing, we selected samples with the following phenotypes: MM (9 samples), MS (9 samples), SZ (3 samples), MZ (11 samples), ZZ (3 samples), and a rare variant (1 sample). DNA was extracted by the standard method. The presence of the AAT Z and S gene variants was determined by the amplification-reverse hybridization test kit, following the manufacturer's instructions, and by the restriction fragment length polymorphism technique, according to established procedures.


RESULTS
We found that the identification of the AAT Z and S gene variants obtained by the amplification-reverse hybridization test kit was completely in agreement with that obtained by the restriction fragment length polymorphism technique.


CONCLUSIONS
We conclude that the test kit provides a fast, easy and unambiguous identification of Z and S alleles. Because of its transferability to routine laboratories, the test kit may be useful in identifying cases of severe AATD, thus resulting in increasing awareness of this rare disorder.
Zorzetto
M
M
Laboratorio di Biochimica e Genetica, Clinica di Malattie dell'Apparato Respiratorio, IRCCS Policlinico San Matteo, Università di Pavia, Italia.
Tamburnotti
C
C
Maschietto
B
B
Massi
G
G
Battaggia
C
C
Medaglia
S
S
Luisetti
M
M
D006801:Humans; D009693:Nucleic Acid Hybridization / Q000379:methods*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011933:Reagent Kits, Diagnostic; D015183:Restriction Mapping; D012680:Sensitivity and Specificity; D000515:alpha 1-Antitrypsin / Q000235:genetics*; D019896:alpha 1-Antitrypsin Deficiency / Q000175:diagnosis / Q000235:genetics*
D011933:Reagent Kits, Diagnostic; D000515:alpha 1-Antitrypsin