Alpha-1-antitrypsin (PiM) subtypes in Japanese

Area of Science:

• Genetics
• Biochemistry
• Population Studies

Background:

• Alpha-1-antitrypsin (A1AT) is a crucial serum protein.
• A1AT deficiency can lead to various health issues.
• Understanding A1AT polymorphism is vital for population genetics.

Purpose of the Study:

• To investigate the serum alpha-1-antitrypsin (Pi system) polymorphism in a Japanese population.
• To determine the allele frequencies of common Pi genes.
• To analyze the inheritance pattern of A1AT phenotypes.

Main Methods:

• Isoelectric focusing (IEF) in thin-layer polyacrylamide gel was employed.
• Serum samples from 335 healthy unrelated Japanese individuals were analyzed.
• Family studies involving 46 individuals were conducted to confirm inheritance.

Main Results:

• Six common and five rare A1AT phenotypes were identified.
• Estimated allele frequencies for PiM1, PiM2, and PiM3 were 0.718, 0.238, and 0.044, respectively.
• Autosomal codominant inheritance was confirmed through family studies with no exclusions in mother-child pairs.

Conclusions:

• The study successfully characterized A1AT polymorphism in the Miyagi prefecture Japanese population.
• The identified allele frequencies provide valuable data for genetic and clinical studies.
• The findings support the autosomal codominant inheritance of the Pi system.