pean populationsthusfar tested and consistent with that of populationsliving near the equator. The distribution of haptoglobin types showed the population to be relatively homogeneous.'* TransJernns in all sera were type CC, the common European type.'* B-Amino-iso-butyric acid urinary levels showed the Marshallese to be the highest excreters of this acid of any population thusfar reported.'* "4 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 that there is probably no correlation with radiation exposure. Hemoglobin types were considered normal (all had type AA,). Sickding 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* anda high frequency of Gm-like (Gm‘).'° Serum studies for the Ag sys- tem reveal that the Rongelapese compared with other world populations have a high frequencyof C.deB. antiserum reactors and a low frequency of New York antiserum reactors.'® Considerable caution 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 andcloset kinship with people of Southeast Asia. These data also may be useful as a base line, should genetic changes appear in later generations, possibly re- lated to radiation exposure. Numerousblood cul- tures for chromosomeanalysis have been taken on past surveys. The results of these studies will be presented in this report. Other Laboratory Studies: Serum protein levels were generally on the high side of normal; electrophoretic patterns showedthe increase in proteins was largely due to an increase in the gammaglobulin fraction. The reason for this is not apparent. Numerouschronic 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 former native diet was probably lowerin salt content than the present more Westernized diet.'* It will be interesting to see whetherthe incidence of hypertension will later increase. 9008241 NOE RR em Ne rn tem eee cen ertmY meee ee + Serum cholesterol levels (1957, 1959) were somewhat lower in 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 generally significantly higher than American levels. The possibility of contamination of the samples with bacteria producing vitamin B,, must be considered, since myeloproliferative and liverdis- eases were notseen. Folic acid levels were found to be somewhat low in the Rongelap population and probably re- flected low dietary folic acid. Serum protein-bound iodine levels have repeatedly been shownto begenerally 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. Glucosuria and elevated blood sugar were found in a numberof Rongelap people. A relatively high incidence 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 pathogensfound, the over-all infection rates were, for Entamoeba histolytica, 18.2%; for hookworm, 5.5%, and for Trichuris trichiura, 34.3%. Eosinophilia (>>5%) has consistently been noted in about half the people. The fact that half the cases with eosinophilia showed nohelminthic infections at all suggests that other factors besides parasitic infections must be responsible. The eosinophilia mayberelated to chronic fungus and other infections, particularly of the skin. Complementfixation studies for parainfluenza1, 2, and 3, respiratory syncitial, psittacosis, and QO fever showedantibodiesto all groups of viruses except that for Asian influenza, which probably had not yet 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 antibody- deficiency-syndrome, but a high frequency of increases of some of the immunoglobulins was noted.