+ + APring Porm: aaaa 38 3, the Micronestans exhibiting the lowest fre- quency. it 1s felt that no conclusions concerning differences between ethnic groups can be drawn at this time. — Table 22 shows the gene frequencies for the six genetic polymorphisms found. e. Blood Studies for Genetically Inherited Traits in the Marshallese.* A large body ofdata has been collected from genetic studies on the Marshallese people. The results are not only of great anthropological interest but also may show in time somepossible genetic effects of radiation exposure in future generations. Table 23 lists the frequency of the varioustraits tested. Blood grouping studies showthat the Marshallese have a relatively high B gene frequency,a high N gene frequency, an extremely high R? gene frequency, and total absence of Kell and Diego factors. These characteristics differ from those of Polynesians and suggest a relationship of the Marshallese people with Southeast Asians and Indonesians. Haptoglobin studies showed a frequency of the Hp! gene higher than in European populations thus far tested and consistent with that of populations living near the equator. The distribution of haptoglobin types showed the population to be relatively homogeneous. 7ransferrins in all sera were type CC, the common European type. fAminoisobutvric acid urinary levels showed the Marshallese to be the highest excreters of this acid of any population thus far reported. Levels in the exposed group were about the sameas in the unexposed group, and no correlation was found with body burdenlevels of radionuclides; this indicates that there is probably no correlation with radiation exposure. Hemoglobin types were considered normal (all had type AAg). Suckéing tests showed no sickling tendency in any of the people. Glucose-6phosphate dehydrogenase of the red cells appeared to be normal in the Marshallese. Studies of Gm phenotypes showed the Marshallese to have 100% Gm‘) and nearly 100% Gm®+). There was a complete absence of Gm? anda high frequency of Gm-like (Gm‘). Serum studies for the Ag system reveal that the Rongelapese compared with other world *We are grateful to the following persons for analyses: blood groupings - Dr. L.N. Sussman, Beth Israel Hospital; haptoglobins, transferrins, AG antigens - Dr. B.S. Blumberg, Institute for Cancer Research, Philadelphia; hemoglobin types - Drs. R.L. Engle, Jr. and G. Castillo, Cornell University Medica! Center, and Dr. §.H. Bayer, Johns Hopkins Hospital; glucose-6-phosphate dehydrogenase studies - Dr. Bayer; BAIB studies - Dr. S.M. Gartler, University of Washington, and Dr. Blumberg. Table 23 Genctically Inherited Traits in Marshallese Trait Frequency (%)} Gene frequency ABO (310 people) O A B AB 60.7 19.7 15.1 4.5 R, P, 0.768 0.128 M N 0.194 0.806 R! R? R®° 0.950 0.020 0.030 Q. 0.103 MN (310 people) M MN N 8.0 22.0 70.0 Kell (310 people) 0.0 Diego (310 people) 0.0 Rh (310 people) Rh,Rh, Rhirhe Rh, Rho Rhg Rho 90.9 4.2 3.9 0.3 0.6 Haptoglobins (176 people) Types 1-1 Types 2-2 Types 2-1 Types 0 & rare 33.5 18.2 47.2 1.1 Ag system (187 people) C.deB. New York 98.0 38.0 Hemoglobin (171 people) AAg 100.0 BAIB(188 people) High excretors 90.0 Australia antigen (474 people) populations have a high frequency of C.deB. antiserum reactors and a low frequency of New York antiserum reactors. The level of BAIB (8-aminotso-butyric acid) was the highest yet reported for any population. Considerable caution must be exercised in evaluating the results of these studies on genetically inherited characteristics because of the small numberof samples tested. The data do seem to indicate relative homogeneity of the population and closest kinship with people of Southeast Asia. St