—— 7 pean populations thus far tested and consistent with that of populationsliving near the equator. The distribution of haptoglobin types showed the population to be relatively homogeneous.'’ Transferrins in all sera were type CC, the common European type.*? B-Amuino-iso-butyric acid urinarylevels showed the Marshallese to be the highest excreters ofthis acid of any population thusfar reported.'’ "* Levels in the exposed group were about the same as in the unexposed group, and no correlation was found with body burden level of radionuclides; this indicates thatthere is probably no correlation with radiation exposure. Hemoglobin types were considered normal (all had type AA,). Suckling tests showed nosickling tendency in any of the people. Glucose-6-phosphate 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* and a high frequency of Gm-like (Gm‘).'® Serum studies for the Ag system reveal that the Rongelapese compared with other world populations have a high frequency of C.deB. antiserum reactors and a low frequency of New York antiserum reactors.'° Considerable cau- tion must be exercised in evaluating the results of these studies on genetically inherited character- istics because of the small number of samples tested. The data do seem to indicate relative homogeneity of the population and closet kinship with people of Southeast Asia. These data also may be useful as a base line, should genetic changes appearin later generations, possibly related to radiation exposure. Numerous blood cul- tures for chromosomeanalysis have been taken on past surveys. Theresults of these studies will be presentedin this report. Other Laboratory Studtes: Serum protein levels were generally on the high side of normal; electropho- retic patterns showed the increase in proteins was largely due to an increase in the gammaglobulin fraction. The reason for this is not apparent. Numerous chronic infections may be an explanation. Sodium levels in the urine and food indicated about the same consumption of NaCl as in Americans. The generally lower incidence of hyperten- sion in the Marshallese might be related to the fact that the formernative diet was probably lowerin salt content than the present more Westernized diet.’ It will be interesting to see whethertheincidence of hypertension will later increase. Serum cholesterol levels (1957, 1959) were some- what lowerin the exposed population than in the comparison or Utirik populations but were in the low normal range. No abnormally high or low readings were noted. Serum creatinine levels (1957) were in the normal range with no abnormallevels noted. Serum vitamin B,,. concentrations (1958, 1959) were generallysignificantly higher than American levels. The possibility of contamination of the samples with bacteria producing vitamin B,, must be considered, since myeloproliferative and liver dis- eases were not seen. Foltc aced levels were found to be somewhat low in the Rongelap population and probably reflected low dietary folic acid. Serum protein-bound todine levels have repeatedly been shownto be generally slightly elevated. Evidence for thyroid dysfunction has only recently been noted in the people along with the recent developmentof thyroid nodules. Thyroid studies will be reviewed in detail in a later section. Glucosurta and elevated blood sugar were found in a number of Rongelap people. A relatively high in- cidence of diabetes is prevalent in the Marshallese people. A survey for intestinal parasites (1958) showed 75% of the people to be infected with various types.'* For the three major pathogens found, the over-all infection rates were, for Entamoeba histolytica, 18.2%; for hookworm, 5.5%, and for Trichurss trichiura, 34.3%. Eosinophilta (>>5%) has consistently been noted in about half the people. The fact that half the cases with eosinophilia showed no helminthicinfections at all suggests that other factors besides parasitic infections must be responsible. The eosinophilia maybe related to chronic fungus and other infections, particularly of the skin. Complementfixation studies for parainfluenza 1, 2, and 3, respiratory syncitial, psittacosis, and Q fever showed antibodies to all groups of viruses except that for Asian influenza, which probably had not vet seriously involved the people of the Marshall Islands. The antibody titers appeared to be somewhatlowerin the exposed people. Immunoelectrophoretic analysis showed neither a paraproteinemia nora typical picture of antibodydeficiency-syndrome, but a high frequency of increases of some of the immunoglobulins was noted.