homozygous for the alternate allele (genotype Au/Au) or heterozygotes
(Aul/Au) do not have detectable Australia antigen (phenotype Au
0)), (4)
Although Au (1) has not been found in normal United States populations,
it is relatively common in some forms of leukemia, i.e., 18% of acute myelogenous leukemia, 17% of chronic lymphocytic leukemia.
It has not as yet been
found in Chronic myelogenous leukemia. A consideration of the United States
data alone, therefore, would suggest that Australia antigen is a leukemiaspecific antigen and may be associated with an increased risk of developing
leukemia. It has also been found in high frequency (approximately 30%) in
patients with Mongolism (Down's syndrome), a disease characterized by a high
risk of developing leukemia. (5
During our studies in Cebu, we found that
Australia antigen is significantly more common in patients with lepromatous
leprosy than those with tuberculoid leprosy or non-leprosy individuals from
the same area.
Consideration of all the patient data suggests that a common factor
in the various diseases in which the trait is found is a deficiency of the
immunological system associated in some as yet unexplained manner with the
presence of Australia antigen. Since the Rongelap people will be medically
examined for many years, it will be of considerable interest to see if there
is a differential susceptibility to disease, particularly leukemia,
to Australia antigen.
.
in respect
In several populations, including Marshall Islanders, a significant
decrease in Australia antigen frequency with age has been detected. This may
be due to selection against individuals with this trait, presumably compensated for by some, at present unknown, selective advantage in respect to one
of the genotypes.
References
1.
Blumberg, B.S., Alter, J.J., and Visnich, S., A "new" antigen in leukemia
sera. J. Am. Med. Assoc., 191: 541-546, February, 1965.
2.
Alter, H.J., and Blumberg, B.S., Studies on a "new'' human isoprecipitin
system (Australia antigen). Blood, 27(3): 297-309, 1966.
3.
Melartin, L. and Blumberg, B.S., Production of antibody against "Australia
4.
Blumberg, B.S., Melartin, L., Guinto, R.A., and Werner, B., Family studies
antigen" in rabbits.
Nature, 210: 1340, 1966.
of human serum isoantigen system (Australia antigen).
Genetics,in press, 1966.
Am. J. Human
5.
Blumberg, B.S., An inherited serum isoantigen in leukemia and Down's
6.
Blumberg, B.S. and Melartin, L., Conjectures on inherited susceptibility
to lepromatous leprosy. Intern. J. Leprosy, 34{1): 60-64, 1966.
syndrome.
J. Clin. Invest., 45: 988, 1966.