A new anodal alpha 1-antitrypsin (alpha 1 AT) variant was identified in a 48-yr-old woman with severe pulmonary emphysema. Isoelectric focusing produced extra bands lying between those of the Pi B and Pi C variants. The new variant was present in 2 of her 3 siblings, 5 of 11 offspring, and probably in her father, all in the heterozygous state. Mean serum alpha 1 AT concentrations and elastase inhibitory capacities were the same in variant and M offspring. The father had reported emphysema, the 2 variant siblings had documented emphysema, and 1 of 5 variant offspring had an area of focal emphysema. The Pi type M sibling and the remaining 10 offspring had no emphysema. Despite normal concentrations and activities, this new variant, which has been designated "Bsaskatoon," may be associated with the development of emphysema within this family.