Alpha 1-antitrypsin-deficient variant Siiyama (Ser53[TCC] to Phe53[TTC]) is prevalent in Japan. Status of alpha 1-antitrypsin deficiency in Japan.
In contrast to the fact that alpha 1-antitrypsin (alpha 1-AT) deficiency is one of the most common hereditary disorders of Caucasians, deficient variants among Orientals have been recognized to be extremely rare. Only 12 cases of alpha 1-AT deficiency have been reported in Japan, including five cases in which the genetic defects have already been elucidated: Mnichinan (delta Phe52[TTC] and Gly148[GGG]-->Arg148[AGG]), two unrelated cases of Siiyama (Ser53[TCC]-->Phe53[TTC]), a heterozygote of Mmalton (delta Phe52[TTC]), and one additional case of 14q- syndrome (sporadic deletion of the neighboring region of the alpha 1-AT gene locus). alpha 1-AT Siiyama is a deficient variant originally identified in a 38-yr-old patient with pulmonary emphysema in Japan. The amino acid substitution in this variant occurs in a highly conserved residue of the serpin (serine protease inhibitor) backbone (Seyama K, et al. 1991. J. Biol. Chem. 266:12627-12632). We attempted to determine whether alpha 1-AT deficiency in Japan was caused by independent genetic defects or whether it shared some common mutations in the alpha 1-AT gene. We examined five of seven available families for which the genetic defects causing alpha 1-AT deficiency have not yet been explored. When the allele-specific polymerase chain reaction (PCR) was performed with a pair of oligonucleotide primers having the mutated base sequence of the alpha 1-AT Siiyama allele at the 3' end, all eight cases of alpha 1-AT deficiency among five unrelated families turned out to be homozygous carriers of the alpha 1-AT Siiyama mutation.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Respiratory Medicine, School of Medicine, Juntendo University, Tokyo, Japan.
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K
Seyama
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Nukiwa
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S
Souma
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K
Shimizu
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Kira
D000328:Adult; D000483:Alleles; D001483:Base Sequence; D005260:Female; D006239:Haplotypes; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008173:Lung Diseases, Obstructive / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D010375:Pedigree; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D011656:Pulmonary Emphysema / Q000235:genetics; D000515:alpha 1-Antitrypsin / Q000235:genetics*; D019896:alpha 1-Antitrypsin Deficiency / Q000453:epidemiology* / Q000235:genetics*
D000515:alpha 1-Antitrypsin; C097145:alpha 1-antitrypsin Siiyama