ABSTRACT
Whereas the gene frequency for the Z-type alpha 1-antitrypsin (alAT)-deficient variant is relatively high (0.01-0.02) among Caucasians, deficient variants out side the United States and Europe-for example, among Orientals-have been recognized to be very rare (1,2). Obviously one reason would be the lack of sufficient laboratory examination systems in countries outside the United States and Europe. However, some countries, including Singapore, Korea, Japan, and Taiwan, have equally sophisticated laboratory examination systems. Nonetheless, only a few cases have been reported except among those of Caucasian descent with the Z deficient variant. For example, only 12 cases with deficient alA T serum levels have been reported in Japan, as described in detail later. More than 2 million Orientals from China, Korea, and Japan-immigrants or their descen dants-live in North America; again, there are only a few reports of alA T deficiency among these U.S. Orientals despite the fact that they receive highquality medical examinations. One null variant, Nullhongkong [two nucleotides’ deletion at residue 318 causing premature termination at residue 334 (3)] was
reported as a variant in a family from China (4). alAT deficiency is also rare in American Indians.
