title: alpha-1 antitrypsin phenotypes by isoelectric focusing in a metropolitan southern Chinese population.
abstract: OBJECTIVE
  alpha-1 antitrypsin (alpha1AT) is an abundant protease inhibitor in human plasma. Its phenotypic variability has been reported to be associated with pulmonary emphysema and chronic liver diseases. However, alpha1AT deficiency is an uncommon condition in the Chinese population. The aim of this study was to describe the phenotypic distribution of alpha1AT in a southern Chinese population.
  
  
  METHODS
  A total of 1085 healthy blood donors underwent alpha1AT phenotyping by isoelectric focusing.
  
  
  RESULTS
  Two thirds (66.1%) were homozygous for either M1 or M2, whereas 32.6% were heterozygous for two different M phenotypes. The frequency of allelic variants was only 0.007, and deficiency variants were absent. Compared with earlier studies on southern Chinese populations, this study found a lower frequency of M2, and a higher number of allelic variants, including E, L, N, P, and S. This phenomenon can be attributed to population migration and mixing.
  
  
  CONCLUSIONS
  An understanding of the alpha1AT pattern is important for evaluating the predisposition of the population to selected clinical diseases.
authors.affiliation: Department of Pathology, The University of Hong Kong, Hong Kong Special Administrative Region, China. microssl@hkucc.hku.hk
authors.forename: S S
authors.initials: SS
authors.lastname: Lee
authors.forename: J W
authors.initials: JW
authors.lastname: Lawton
authors.forename: K H
authors.initials: KH
authors.lastname: Ko
authors.forename: K M
authors.initials: KM
authors.lastname: Lam
authors.forename: C K
authors.initials: CK
authors.lastname: Lin
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D005260:Female; D006579:Heterozygote; D006720:Homozygote; D006723:Hong Kong; D006801:Humans; D007525:Isoelectric Focusing / Q000379:methods; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D000515:alpha 1-Antitrypsin / Q000235:genetics*
chemical_list: D000515:alpha 1-Antitrypsin